Hopeshredder/Arborix Raider | 1.5M Shaper | Ice Shot + Barrage | PoB Link Provided | 25-40ex Budget

+ Clears all story and T1-T15 map content with minimal effort (includes Pale Court, regular Atziri)

+ Clears all end game content with slightly more effort (Shaper and Shaper/Elder guardians take significant effort, while uber Atziri/uber Elder take even more effort)

+ Compatible with MF (magic-find) cullers who don't do damage but have insane amounts of IIQ/IIR (increased item quantity/increased item rarity) to compensate (due to Southbound cull trick)

+ Uses four elder-related unique items, in case you wanted to try them all out in one build (Hopeshredder, Arborix, Voidfletcher, Mark of the Elder), with the option to use two more elder-related unique items if you allocate passives or get other good gear to balance resistances and maintain high life (Yoke of Suffering, Cyclopean Coil)

+ Uses unique items in every slot except 1 ring and belt; dependence on uniques means lower cost and possibly higher effectiveness than well-crafted rares that might exceed 1-2ex in value

+ Costs about 25-40ex to fully build (budget section explains cost calculations) and provides both decent AoE damage and single-target damage

+ Allows for quick kiting with 2 movement skills that can be used in tandem/alternating (due to Illusory Warp granted by Star of Wraeclast amulet)

+ Higher cap for cold resistance (81% default, 87% with sapphire flask), allowing you take less damage from uber Elder and Shaper cold fields

+ Resistant to one-shots (due to Arctic Armour LESS physical/fire damage taken, Kintsugi 20% LESS damage from hits if not hit recently, Arborix temporary Iron Reflexes)

+ High movement speed without adrenaline flask (due to frenzy charges, Hopeshredder bow 4% movespeed/frenzy charge mod, Arborix temporary 30% movespeed boost)

+ Elemental ailment immunity without heat/grounding/dousing flask, allowing for use of Ample Diamond Flask of Warding (due to raider ascendancy, if you take Avatar of the Veil)

+ Near-capped projectile evasion/avoidance without using Jade/Stibnite flask (due to raider ascendancy, if you take Avatar of the Chase)

+ Near-constant uptime of Onslaught when killing mobs (either from Avatar of the Chase pathing or using Silver flask, see Flasks section)

+ Enhanced/doubled life leech rate (as a result of Vaal Pact - helps you bounce back from those near-death scenarios)

- Lower-end life without good gear (around 5-5.5K)

- Not ideal for newer players who don't have the funds to obtain 3 6-links; cheaper gear or 5-links drastically reduces potential DPS output

- Not ideal for players who aren't inclined towards mechanically intensive play (in maps, requires 4 finger taps on keys 2,3,4,5 every 3-4.5 seconds; 2 finger taps on keys W,E alternating every 1.5-2 seconds; 1 finger tap on key T every 10 seconds -- to maintain high DPS)

- Non-compatibility with MF (magic find) gear (because every piece of gear has a specific and near-irreplaceable purpose)

- Cannot do maps with elemental reflect mod without multi-exalt investment (due to not-full immunity to reflected elemental damage, maximum if you were to use Sibyl's Lament instead of Mark of the Elder ring is 75%, can go to 100% if you were to invest in a shaper unset ring with +3 socketed gems prefix and 25% reduced reflected damage taken suffix -- not worth)

- Struggles with maps with chance to avoid elemental ailments mod (reroll map or use DoT-inflicting skill - see Gem Links section for how to compensate for this)

- Not immune to bleed (must take Panicked/Seething Divine/Eternal Life Flask of Staunching)

- Not immune to elemental ailments if you take Avatar of the Chase instead of Avatar of the Veil (must take Ample/Experimenter's Diamond Flask of Heat, as opposed to Warding counterpart)

- No life regen (as a result of Vaal Pact - may require you to change your flask setup when going through merciless/eternal labrynth)

- Lower physical damage reduction than you might want (2% by default, but temporary Iron Reflexes from Arborix, mitigates this)

- Requires someone else to have done Elder guardians, white/yellow/red Elder, and Uber Elder to get particular pieces of the gear (relevant to temporary league pricing)

- Balancing resistances (especially lightning, in this case) can be tough

Since some people I've met (myself included) have had no idea what Path of Building is, I am also including a link to installation. To beginners and newcomers to PoB - welcome; consider this tool to be an enhanced build planner for items and passive tree.

Path of Building GitHub Main Page: https://github.com/Openarl/PathOfBuilding
Path of Building GitHub Releases/Download Page: https://github.com/Openarl/PathOfBuilding/releases

My build Pastebin: https://pastebin.com/42cD7d8H

For those who simply want to highlight and copy:
https://pastebin.com/42cD7d8H

How do I use this Pastebin link?
Once you open PoB and create a new build, you should see a vanilla/empty build screen.
Go to Import/Export Build > Import from Pastebin... > paste (ctrl/command-V) link > press OK > press Import > Enjoy!)

Helmet:

• Starkonja's Head is best-in-slot considering it gives life, offensive, and defensive capabilities. The downside is the 50% reduced damage when on low-life, which is compensated for by intelligent flask management (see Flasks section below) and Vaal Pact to leech back quicker.
• Rat's Nest is the next-best-in-slot, considering it gives offensive and defensive capabilities. The downside is lack of life.
• Third best in line is Devoto's Devotion. Upside is faster movement and attack speed and footstep MTX. Downside is reduced physical damage, which spills over into reduced DPS overall due to the way damage conversion works (if I recall correctly).
• What's best after this is really up for speculation. Could go for a rare helm with life and resistances if it's cheap enough for you.
• Geofri's Crest comes to mind as an all-around slightly-useful unique due to the resistances it provides, if you can't afford the above (which you should, they're 5-10c sans enchant).
• Same comments for Geofri's Crest also apply to Alpha's Howl, but Alpha's Howl enhances your auras instead of your resistances. Both are okay but discouraged in practice if you can afford #1 and/or #2.

Body Armour:
Note1: Items shown above are not all 6-linked; they are just there to provide a baseline / visual of what you might like to choose.
Note2: Body Armour can be chosen at your discretion.

• Kintsugi 6L seems/seemed to be the best choice for this build due to the 20% less damage taken if not hit recently. This modifies the Hopeshredder cold damage over time (see Bows section below) to work at 80% of its strength, allowing you 25% more time to regain that health back, either by leech or by hitting flask. Not to mention, this also makes one-shots less one-shotty. This is the body armour which I worked with.
• Belly of the Beast 6L is a strong and viable alternative to increase your life pool, if you aren't worried about the Hopeshredder cold damage over time. Almost forgot to mention it helps with resistances too. There may be debate as to whether Belly or Kintsugi is better for overall survival, but I'm not going to be a part of that argument, as I have both (:D).
• Yriel's Fostering 6L is yet another powerful alternative, but it will feel more glass cannon-like. The offensive benefits are accuracy and added phys/atk speed depending on which variant you've taken. The defensive trade off is slightly more life, but less fire resistance and evasion.
• Snowblind Grace 6L is a possible choice for more spell dodge and enhanced Arctic Armour, but evasion is inferior.
• Perfect Form 6L is a possible choice to save you the passive point from taking Phase Acrobatics keystone, with free Arctic Armour mana reservation, but evasion is inferior and you lose cold resistance. Sometimes I feel that I don't understand why people upgrade from Snowblind Grace to Perfect Form, considering the marginal benefits (yeah, I know the mana reservation = 0% can be pretty big, but still).
• Hyrri's Ire 6L is an often underrated choice, and I advocate it if you want to make the build more of a glass cannon. The added cold damage and chance to dodge attacks and spell damage are very useful to our build. Yet, we don't get any life, making this a slightly less optimal choice compared to even Yriel's Fostering. That being said, I did use this with a Raider using White Wind for capped attack dodge at all times, without flask or Vaal Grace. Very powerful defense mechanism indeed.
• Skin of the Lords/Loyal/Tabula Rasa auto-6L. Why am I writing about these? They aren't useful to our build, even if you like the 100% global defenses mod. (This is a noob trap I fell into in Legacy league when I started; let me wallow in shame alone.)
• Farrul's Fur 6L. I hear it's strong and allows for charges to be gained and maintained even in boss arena. It appears to have life, which is good. Evasion is inferior to Kintsugi. However, the benefit of Aspect of the Cat is the charge generation, which we automatically have for frenzy from Raider. If you were to take another ascendancy or class, this might become best-in-slot (see FAQ for comments on ascendancy choice).
• Shroud of the Lightless 5L6S. I hear that people like it. I think it's a bunch of hype. Sure, abyss jewels are strong. But doesn't mean you have to stick it everywhere. (insert obligatory phallus reference here) But, on a more serious note, it makes it harder for you to build the Ice Shot Mirage Archer setup with similar DPS (you'd have to drop Faster Attacks in that case; see Gem Links section).

Rings:

• Optimal setup appears to be Mark of the Elder Steel Ring and a shaped rare Unset Ring with +3 to socketed gems.
• Why Mark of the Elder Steel Ring? For heaven's sake, please see the added physical, added cold, increased life%, increased attack damage when other ring is a Shaper item, and the extra Tentacle Whip for pure hentai fun. (p.s. If this goes on BoTW, Bex doesn't have to mention the hentai. But it would be great for the memes/PR!)
• Why shaped ring, can't it be regular? No! We want to utilize the increased attack damage mod on the Elder ring. If you happen to value the cannot be stunned by attacks mod, I suppose an elder ring could also work.
• Why unset +3 to socketed gems? Can it be +2 to socketed gems? Purpose of +3 is to free up gem slots to avoid using Empower + Purity of Ice combination to get your maximum cold resistance to high levels. Level 23 is the level required to obtain +5% to maximum cold res as opposed to +4%. Therefore, hypothetically, if you were to get a level 21 Purity of Ice, you could use a +2 to socketed gems.
• How did you get that ring crafted? I spammed 5-8 deafening essences of hatred until I hit +3. Then I crafted the open suffix to lightning resistance since it was the only resistance that I had unbalanced. You will probably have to do the same if you follow my tree. Total cost of crafting was 20c for the base, 50c for the essences, and priceless luck. Instead of using essences you can also try chaos spamming, the plebeian way to "craft".
• If you wish to be totally lazy about resistances, you can use a Le Heup of All or a Ventor's Gamble instead of Mark of the Elder. But then I'd call you a proletarian since your damage wouldn't even be middle class.
• Before thinking of using Mark of the Elder, I was using a half-decent breach ring, linked above. If you wanted to, you could run with any of these in breachstones for the double-bonus implicit activation and farm breachstones. This build is capable of completing solo runs of Tul, Esh, Xoph, and Uul-Netol, deathless.
• Do not try running Voideye or Essence Worm. While they have their uses, they aren't ideal for this build - they will mess with your mana reservation and/or resistances.
• The Taming is a possible option for +40% to all resistances, elemental damage with attacks, elemental damage to enemies inflicted by ailments. Would be interesting to farm a Shaped Berek's Pass, Berek's Grip, Berek's Respite using Trash to Treasure (x3-5, depending on your RNG) on Shaped Two-Stone Rings, then trade in for Shaped Taming - then you could replace the unset ring, and then move Purity of Ice somewhere else. You would lose +1% to maximum cold resistance, but in exchange for lots of damage, and less worry about resistances. But this is super costly - don't do it!

<<add nomad,tactician>>
Belt:

• Rare (potentially Elder) Leather belt with T1 Fire Res and T1 Lightning Res and T1-3 Life should be good. Optional mods include elemental damage to attacks, flask duration/effect, energy shield. If you happen to be essence crafting for that Russian roulette feel in your virtual wallet, get strength (for more passive life) or intelligence (to save passive points).
• Alternative is a rare Stygian Vise Belt with similar mods as mentioned above.
• If you can't afford to craft either one, go for a Doryani's Invitation, cold variant, for that sweet T3 fire and lightning resistance. This means you will have to work extra hard on getting higher fire and lightning resistances on your ring (which Elreon has as an actual mod, so if you have open suffix with lightning res as another suffix, you're saved! I think.)
• Headhunter doesn't belong here. Its cost encompasses the whole budget of the build; why would I put it here?
• If by some miracle of a ring or jewel on tree, you don't have to worry about resistances, you may consider unique belts. I list them below.
• Darkness Enthroned. The right place to put Abyss jewels. (In fact, in retrospect if you have a good pair of 4-mod Abyss jewels, of which one mod in each is fire + lightning resistance, then this might be the way to go. Of course, if another of those mods isn't life, you're just making this build more glass-cannon-like.
• Gluttony. If you aren't going to have armour or energy shield, you might as well use this belt if you want to try more uniques out. Gives up to 120 flat life, which scales to about 300-400+ life. Only issue is that it'll override your CWDT-linked Projectile Weakness curse, which you can replace with Immortal Call to synergize with Gluttony.
• The Nomad. Definitely a great idea as it gives passive life from strength, flask charges gained, elemental resistances if you hit the minimum strength limit, and projectile attack damage if you hit the minimum dexterity limit (which you certainly will).
• The Tactician. Weaker than The Nomad. Almost the same mods but gives intelligence. Unlikely that you'll hit the minimum intelligence limit for the bonus critical strike chance unless you invest 2 passive points into 2 +30 intelligence nodes.
• Cyclopean Coil. More tentacle action, but around your waist. I could have added this to the build to advertise that this uses 5 elder uniques, but I passed in favor of at least one piece of rare gear. If I were to obtain a ring/pair of jewels with high fire and lightning resistances, I'd go for replacing the belt. But such a combination is hard to find or costly. Advantage of this belt is high life and scaling to attributes with some marginal increase in damage.

<< AMULET LINKS GO HERE >>

Amulet:

• Star of Wraeclast. Benefit is the extra movement skill to kite around. If you don't like that kind of gameplay and were looking for more lazy, RF-style gameplay, please seek another build. Also gives up to 75% total resists and up to 50% increased cold damage. There is a recipe for this, you can find it here: https://pathofexile.gamepedia.com/Star_of_Wraeclast
• The Pandemonius. Benefit is the extra cold damage, cold penetration, elemental ailment (chill) infliction, blind to make evasion/dodge more effective. If you don't like Star of Wraeclast, you'll like The Pandemonius more.
• Yoke of Suffering. Has attribute gain, resists, increased damage taken by enemies per ailment (which would be chill/freeze/shock, so max 15%). Probably the cheapest of the uniques here, with the added benefit of resistances but detraction of no life (guess it's why it's called Yoke of Suffering).
• Rare amulet with critical multiplier, critical chance, life, resistances and/or added physical or cold damage also works. Make sure you have life, otherwise it's not any better than Pandemonius.

<< GLOVE LINKS GO HERE >>
Gloves:

• Southbound. High added cold, high life added, high cold resistance to ensure Wise Oak penetration mod affects cold damage, increased damage with Herald of Ice. All good. Except the annoying hits-only-kill-frozen-enemies, which makes some people think that their game is broken. (another noob trap, beware) Get past this by getting a DoT skill to "cull" mobs. I use Decay on Tornado Shot with Chain for when I run into mobs that resist elemental ailments, leaving them at 1 HP even when I hit them with Ice Shot sans Elemental Focus.
• Rare Gripped Gloves are the only other good alternative, if you get tired of the hits-only-kill-frozen enemies debuff from Southbound. You'll need resistances, as other uniques lack them (this is why you do not see a 2-socket Tombfist in this category). Nice mods include life, added physical damage, added cold damage, resistances, attack speed.

<< BOOT LINKS GO HERE >>
Boots:

• Best-in-slot for any Raider taking advantage of frenzy charge scaling is Darkray Vectors, preferably with +1 frenzy corruption to get a net +2 frenzy on boots. If this isn't on your shopping list, it takes 2-3 ex off of your budget.
• Rare Two-Toned Boots provide lots of resistances if you craft them well/luckily. Consider this as a highly defensive alternative, as you can also get life in this slot. But the damage won't compare to as if you were using Darkray +1s.
• <<revise>>

Bow:

<<revise>>

Quiver:

• A Rare Quiver should have Life, Elemental Damage with Attacks, Crit multiplier and Attack speed.
• A Rare Shaper Quiver should have Additional Arrow, Life, Elemental Damage with Attacks, Crit multiplier and Attack speed.
<<revise>>

Abyss Jewels:

• Life > Flat Ele To Attacks/Bows > Attack Speed > Crit Multi > Res if you need it

Jewels:

• Life > Attack Speed with Bows > Attack Speed > Crit Multi > Res if you need it

1 - Panicked Divine Life Flask of Staunching (must have for anti-bleed)
2 - Chemist's Diamond Flask of Heat (must have for anti-freeze)
3 - Taste of Hate Sapphire Flask (must have for mitigating anti-cold DoT from Hopeshredder)
4 - Dying Sun Ruby Flask (good to have for DPS + clear)
5 - The Wise Oak Bismuth Flask (good to have for bosses and elemental weakness maps)

This is what I believe to be the optimal flask setup, but if by any chance you feel that you want to change it for budgeting reasons or whatnot, there are definitely cheaper alternatives for each slot.


A1 - Saturated Eternal Life Flask of Staunching (need anti-bleed suffix, minimum. Divine is better than Eternal for this build since Panicking/Seething Divine gives more instant life recovery than Panicking/Seething Eternal. But if for any reason you want the Saturated prefix, Eternal wins out.)


A2 - Experimenter's/Chemist's Diamond Flask of Warding/Adrenaline (if you take Avatar of the Veil ascendancy instead of Avatar of the Chase, you open up suffix since you no longer need Heat)
<<no examples here>>
A3 - Experimenter's/Chemist's Sapphire Flask of Warding/Adrenaline/Heat/Reflexes (if you want to sub out for a cheaper flask but retaining the +6% to maximum cold resistance; the DPS loss is like 1-3%)


A4 - Rotgut Quicksilver Flask or Experimenter's/Chemist's Silver Flask of Warding/Adrenaline (again, if you take Avatar of the Veil ascendancy instead of Avatar of the Chase, you need a way to get back Onslaught)


A5 - Experimenter's/Chemist's Jade/Quartz Flask of Warding/Adrenaline/Heat/Reflexes or The Overflowing Chalice Sulphur Flask

If I were to try to put really cheap flasks in each slot but get maximum benefit out of them, it might look like the below:

Poor man's Avatar of the Chase version of flask setup (no elemental ailment immunity affects flask choice)

<<chem sapp heat flask>><<oc unique flask>>

1 - Panicked Divine Life Flask of Staunching (must have for anti-bleed)
2 - Chemist's Diamond Flask of Warding (must have for anti-freeze)
3 - Chemist's Sapphire Flask of Heat (must have for mitigating anti-cold DoT from Hopeshredder)
4 - Chemist's Jade/Quartz Flask of Reflexes/Adrenaline (defensive option)
5 - The Overflowing Chalice Sulphur Flask (for refilling other flasks + small damage boost)

Poor man's Avatar of the Veil version of flask setup (no reliable source of Onslaught affects flask choice)

<<chem sapp reflex flask>><<oc unique flask>>

1 - Panicked Divine Life Flask of Staunching (must have for anti-bleed)
2 - Chemist's Diamond Flask of Warding (must have for anti-freeze)
3 - Chemist's Sapphire Flask of Reflexes (must have for mitigating anti-cold DoT from Hopeshredder)
4 - Rotgut Quicksilver Flask / Chemist's Silver Flask of Adrenaline (gotta go fast)
5 - The Overflowing Chalice Sulphur Flask (for refilling other flasks + small damage boost)

Bow 2: Arborix
Setup 1: Elemental Damage (when not mapping solo)
Tornado Shot - Ice Bite/Added Cold - Elemental Damage with Attacks - Elemental Focus - Greater Multiple Projectiles - Chain/Pierce

Setup 2: Chaos DoT Damage Cull (when mapping solo / Southbound being a nuisance)
Tornado Shot - Decay - Swift Affliction - Void Manipulation - Greater Multiple Projectiles - Chain


Body Armour
Ice Shot - Ice Bite - Elemental Damage with Attacks - Increased Critical Damage - Mirage Archer - Faster Attacks



For partnering with MF cull builds, run Elemental Focus instead of Increased Critical Damage. Both are blue gems, so no chromatics need to be wasted.

Helmet
Blood Rage - Vaal Haste - Blink Arrow - Enhance



Enhance:http://www.pathofexile.com/trade/search/Standard/mlbgehn


Gloves
Arctic Armour - Herald of Ice - Enlighten - Portal



Boots
Cast When Damage Taken - Projectile Weakness - Summon Ice Golem - Frost Bomb

1 - Panicked Divine Life Flask of Staunching
2 - Chemist's Diamond Flask of Heat
3 - Taste of Hate Sapphire Flask
4 - Dying Sun Ruby Flask
5 - The Wise Oak Bismuth Flask
LMB - Ice Shot (common to both weapon setups)
MMB - Portal (common to both weapon setups - quality of life so you won't waste $$$ on portal scrolls)
RMB - Barrage/Tornado Shot (press X to switch weapon setups)
Q - Herald of Ice + Arctic Armour + Purity of Ice Auras (before starting combat, activate each aura in succession, replacing the previous aura with one that isn't activated - this allows you to use other keys for skills)
W - Blink Arrow
E - Illusory Warp
R - Blood Rage
T - Vaal Haste

In the end, should look like this, with exception of Q:

• Alternate between Blink Arrow (W) and Illusory Warp (E) for when your frenzy charges are down, or if you want to go even faster. Make sure to time each in staggered succession, i.e. each gets activated 1.5 seconds after the other, so movement is a bit smoother.
• Another possible way to maximize utility of having access to two movement skills is to use one movement skill (i.e. Illusory Warp, since it gets you out of harm's way faster) to move away from a boss (e.g. Shaper) when they are channelling a one-shot skill (e.g. Shaper slam/beam), and use the other skill (i.e. Blink Arrow) to get in front of them again when there is less danger to make optimal use of the Point Blank passive.
• Default bow setup to use when solo mapping is Arborix, for the free 8 second 30% attack + movement speed buff alternating with Iron Reflexes. Clear with Ice Shot; use Tornado Shot Decay setup to finish off kills if Southbound is being a problem because you don't have enough freeze chance.
• When partner mapping with a MF (magic find) cull support that has no/low damage, replace Increased Critical Damage Support with Elemental Focus. This allows you to utilize Southbound's hits-only-kill-frozen-enemies mod to your benefit, allowing kill credit to go to the MF build with higher IIQ/IIR. Make sure to split the drops/profits in an envy-free way!
• Use Blood Rage and/or Vaal Haste in boss arenas, breaches, or breachstone-like settings, for faster clear and completion. This build has been tested up to Uul-Netol, deathless.
• Make sure to ensure permanent flask uptime by constantly killing mobs. I try to keep pressing keys 2 through 5 every 4-5 seconds to maintain high DPS.
• To ensure even higher DPS, you can also run Vaal Haste every 10 seconds (or less).

Note that in subsequent sections, enchantments will be listed from best to worst. Some judgments may be based on empirical calculations, others by intuitive convenience.

Helmet:

<< IF AIMING FOR SINGLE TARGET EMPHASIS >>
1-2 Additional Barrage Projectile (2 is legacy, probably not worth using on this build)
25-40% increased Barrage Damage
10-15% increased Barrage Attack Speed

<< IF AIMING FOR MULTI-TARGET/AOE EMPHASIS >>
25-40% increased Ice Shot Damage
8-12% increased Ice Shot Area of Effect (needs more testing to definitively conclude it's useless, but I am not without hope! :D)

1-2 Additional Tornado Shot Projectiles
25-40% increased Tornado Shot Damage
60-90% increased Tornado Shot Critical Strike Chance

<< MISCELLANEOUS >>
Blood Rage grants additional 8-12% increased Attack Speed (slightly more damage output against mobs)
20-30% increased Projectile Weakness Curse Effect (slightly more boss damage)
30-45% increased Projectile Weakness Duration (slightly more boss damage)
100-150% increased Effect of the Buff granted by your Ice Golems (slightly more damage overall)
20-30% increased Blink Arrow Cooldown Recovery Speed (more kiting potential)
24-36% increased Arctic Armour Buff Effect (more resistance to physical damage one-shots)
20-30% reduced Arctic Armour Mana Reservation (more mana for players with less leech available, may allow for a Clarity Gem to be slotted in)
25-40% increased Herald of Ice Damage (more clear potential against mobs)
20-30% reduced Herald of Ice Mana Reservation (more mana for players with less leech available, may allow for a Clarity Gem to be slotted in)
20% reduced Purity of Ice Mana Reservation (more mana for players with less leech available, may allow for a Clarity Gem to be slotted in)

Gloves:

Word/Edict/Decree/Commandment of Reflection (free mirror arrow clone for when you get hit essentially, might temporarily distract some aggression from mobs/boss)
Anything other than Word/Edict/Decree/Commandment of Light will be OK though (because if you do take a critical strike to get the Light enchantment bonus, you're probably already dead)

Note that you don't want enchantment on rare Gripped Gloves, as this will overwrite the 15-18% increased projectile attack damage implicit. A friend of mine made this pitiful mistake, don't do the same!

Boots:

<< IF AIMING FOR SINGLE-TARGET EMPHASIS >>
Damage Penetrates 10% of Enemy Elemental Resistances if you haven't Killed Recently

<< IF AIMING FOR MULTI-TARGET/AOE EMPHASIS >>
16% increased Attack and Cast Speed if you've Killed Recently

<< MISCELLANEOUS >>
Regenerate 1-2% of Life and Mana per second if you were Hit Recently
0.4-0.6% of Damage Leeched as Life and Mana if you've Killed Recently
Adds 16-45 to 24-68 Fire Damage if you've Killed Recently

Bandits:
Exterminate all 3 bandits for 2 Skill Points, this is simply the most efficient way.
Possible to help Alira only for the critical strike multiplier and elemental resistances (no one cares about that mana regen at higher levels), but it's just an inferior choice compared to the versatility of 2 passive points

Pantheon:
For Major God: Soul of Lunaris (for mob-clearing) or Soul of Arakaali (for general mob-clear and boss fights)
For Minor God: Soul of Yugul for reduced elemental reflect.

Explain your choice of ascendancy. More specifically, why not Pathfinder, Deadeye, Trickster, or Scion Ascendant?

Choosing Pathfinder requires more investment to scale properly, and such investment would go over the 25-40ex budget as claimed by this post. Reasoning - if you wanted to make this build shine like other build guides that advertise even 5M+ DPS, you'd want at least close-to-mirrored gear and legacy flasks. The only legacy flask I use is The Wise Oak, which in itself costs 1ex at time of writing. A truly legacy flask setup to launch the DPS sky-high would be:

1 - Legacy Vessel of Vinktar Topaz Flask Attack variant (265ex)
2 - Legacy Taste of Hate Sapphire Flask Perfect roll (15ex if relic foil)
3 - Legacy The Wise Oak Bismuth Flask (1ex)
4 - Legacy Dying Sun Ruby Flask Reduced Charges (2-3ex minimum)
5 - Legacy Atziri's Promise Amethyst Flask Perfect roll (1ex)

Sure, if you have these flasks and a belt like Skalpo's Stygian Vise with flask effect and duration mods, go ahead and take Pathfinder. But you'll lose one frenzy charge, which was my intention for choosing Raider.

~~

Choosing Deadeye when there's no clear path to scaling and clear loss of near-permanent Onslaught/phasing, 1 frenzy charge, and/or elemental ailment immunity. The only benefits I can see from choosing Deadeye are extra chain, tailwind, +1 projectile, and blink arrow cooldown recovery. Cost and benefit analysis points in the direction of Raider being the superior choice, in my opinion - though you're free to disagree or make PoE an even bigger challenge for yourself.

~~

Choosing Trickster has some mildly clear path to scaling given its RNG-based non-chaos % gets added as chaos damage and extra frenzy and power charge. Moreover, it has some evasion/dodge granted with some ES. I haven't looked into the full potential of this choice, but it still seems inferior to Raider, as its lack of proximity to life nodes will make it squishier if you plan to follow the build guide and make this a life-based build.

~~

Choosing Scion Ascendant can be decent, and it's probably the second-best class I'd advocate for someone trying out this build. I'm a huge proponent of Scion, so it's highly likely that I'll make a second tree for Scion Ascendant. But possible sub-ascendancies include, from most to least desirable:
Primary: Raider (all-around) > Deadeye (short boss fights) >= Pathfinder (extended uber boss fights)
Secondary: Inquisitor (close quarters combat, ailment immunity, consecrated ground + regen) >= Elementalist (all-around, reflect immunity) > Juggernaut (physical damage reduction) > Berserker (all-around, glass-cannon)

While you potentially lose ailment immunity and some frenzy charge scaling and permanent onslaught, you gain more life due to proximity to the f**k-ton-of-life cluster. Regen nodes also help you lose Vaal Pact.

Isn't 4.5-5.5k life for levels 80-100 low?

Yes, by a rich/well-off player's standards, this is going to be fairly low. However, considering that this build stacks high evasion, decent dodge, and mechanical kiting through 2 movement skills, I feel that I've compensated for it sufficiently.

Is Headhunter or Atziri's Acuity required to make this build viable?

No. It's just quality of life - if you have it, great. If you don't have it, then you'll still live.

Do I need the +2 Barrage/TS Enchant or +1 Quiver to make it work?

+2 Barrage is not needed but is a great asset to have. Same with +1 Quiver.
A good rare with Wed/Crit Multi/Life/Ele Rolls will be better than a non +1 Quiver.
Rigwalds quills is another good option if your only focusing on mapping as it gives a free fork to your skills

Is this a Good League Starter Build?

I doubt it is

Can i use a Drillneck?

No! Drillneck only has AS and life going for it, a rare Elemental quiver will always be better.

How Expensive is this Build?

See budget calculation section. It can be as cheap or as expensive as you want it to be, but it will change the effectiveness of this build. I think I've hit the sweet spot with around 25ex of gear, while still holding true to use of 4 elder uniques, which was the original purpose of this build.

How do I squeeze out more DPS while maintaining effective HP count? (assume I'm rich af btw)

Perfect DPS/numbers on all gear. +1 arrow Voidfletcher/Drillneck. Multi-exalt Abyss jewels with life, added phys, added cold, crit multi, % life regen.

Mirror-tier shaped unset +3 ring with Essence of Hatred mod, mirror-tier quiver with Essence of Horror mod + additional arrow to continue cold damage per frenzy charge stacking, mirror-tier stygian vise/elder leather belt with tier 1 elemental damage to attacks and/or flask effect + duration. Make sure all rare gear has tier 1-2 life.

Mirror-tier amulet. See Ahfack's Viper Beads or Rayamn's Vengeance Collar as examples. Note that you'll lose the second movement skill if you pursue this path; substitute Portal with Flame Dash and Enhance with Portal in this case; then Flame Dash will supplant Illusory Warp in your keybinds.

Why not Lioneye's Fall jewel on the projectile damage cluster at the far right of tree with claw leech + crit chance + multi, as many other bow builds do?

We can get life and mana leech from other nodes. According to PoB, the damage nodes provide a roughly 15-18% boost to DPS over 8 nodes of investment, which averages out to 1.875-2.25% DPS increase per node. I like to take nodes/node clusters with 2.5% DPS or more increase per node when building characters, as it helps me establish a baseline for when to stop chasing DPS and accumulating life instead. So that's why I didn't adopt that strategy - not to mention the added 1ex cost of the jewel in Standard.

Do I absolutely need Point Blank? Can I do without it? Because it seems weak to me...

Any reason for it feeling weak to you is because you have low proximity to your enemies. Use the 2 movement skills I've provided to kite around and in front of them to maximize DPS.

That being said, point blank is a 1-node investment for around 30%-more damage if you are right in front of your enemies.

Don't use Point Blank if you plan to use the build for maps only with no boss interactions.

Continue to use Point Blank if you plan to use the build for all content.

What About +1 Frenzy Dark Ray Vectors?

Use the if you have em. Great pair of boots for the build as they give alot of dodge and damage from frenzy charges.