Destructive link - combatant ( upgrades )

Hey,

i've been slapping around with combatant and i wanted to ask whether i missing something obvious. Map clear is great and all that but mainly it feels like my merc sometimes deals good single target damage and something misses 8 times in a row.

Pob'd everything to best of my knowledge (multistrike aside), and it says hit chance is 100%, crit is always 100%, damage roll (spread) is not THAT big. It also says dps is around 3 mil.
More than enough to clear regular maps but i do want to push it further.

Anyway,
merc pob : https://pobb.in/7Q5LC8CBd5kU

Upgrades i've considered are mainly the gloves with - socket + some useful stats.
Is there anything that beats paradoxica?

Aurabot (main char) pob : https://pobb.in/d8G4NizehKvd

Upgrades i've considered - +2 all +2 lightning amulet. With level 21 precision and crit suffix on flask my crit will be around 90%. +2 min power charges on suffix should make it 100.
Higher es body and helm - obvious.
Elevated aura effect +1 int gems on body armor.
Vestigial aegis aurora with 10% aura effect - very expensive.
Pushing aura effect to x2.5 (its 2.25 atm) for break point on necro jewels.

Build in action;
uber feared
uber cortex
uber dread

uber sirus is a dog fight.
uber shaper and elder are not really a dmg check.

Overall i feel like damage should be able to go like x5 but im missing something.
Low damage is especially visible in uber dread fight where merc also managed to die once.

Again, i've set up pob config to best of my knowledge, gem levels are representative of merc links
(he also has static strike with more duration) - upgrading merc after this point is rather expensive, 200+ div.

I'd appreciate any insight.
Thanks!