Build Help - Mana Stacking Brand Heir

So I've been theory crafting a mana based build ever since I saw the new mana based gems.

I've come up with this PoB: https://pastebin.com/mW5FBJ6w

My brand is currently on a 5 link as we don't have the archmage support in PoB yet but the damage seems kinda low, with 9k mana i'm sure it'll add a big chunk but will it be enough?

Any other feedback is appreciated too. I'm trying to go for a league starter here, so not looking big expensive unique for the build. The uniques already there are just "chase" items, I think the build should work fine with any rare which comes with a large chunk of mana.

Cheers guys (and gals).

If you are looking for advice than i would say that, sadly, but poh spell echo doesnt affect brands activation, so everything that you get from it is increased mana/spell damage and 150% mana multiplier from 7th link, which is really good but imo better options exst. It's kinda neccessary to link brand recall on something with +# to socketed gems, to get increased cd recovery, so you may want to use eclipsis shield or +3 crafted wand (most probably not needed anymore because of second wind, if it works).
Also seems logical to use items with increased mana cost (voidbringers/indigon) to get as much benefits from archmage and mana pool as possible.
I would also advice to drop some mana/hp nodes on your tree and get more damage nodes (crits/lightpen/+1 brand). It looks like you will be lacking of damage wtih your current pob dps (even with archmage support, by my roughly countings you will get around 1500 flat lightning from it), at my expireince you will need at least 300-500k effective dps for endgame.
And sorry for my english skills, its not my native language