Does Merc physical damage build fall off more and more as you level?

I'm only mid 30's and my gear is bad so hard for me to tell if this is a class thing or gear thing but the more I level the worse my character is feeling. I do see a boost in power when I get an actual weapon upgrade but it falls off fast with a few levels and I rarely find upgrades (and not near enough currency to craft with).

I was just trying to focus on projectile damage, reload speed, attack speed, physical damage type nodes and use fragmentation rounds, armor piercing rounds and high velocity rounds. That was OK earlier but they feel like they are getting weaker as I level. Galvanic Shards feels more powerful and I have invested nothing into lightning damage so it just feels odd that that a lightning based skill is my best damage (and not good on single target).

I did also try bleed because that seemed like a logical ailment to pair with physical damage and APR but that also felt quite bad. I guess bleed damage is tied to the damage of the skill that applies it (not having multiple instances) so APR is great for applying bleed but it does pitiful damage.