I don't think the abilities need to be anything like sniper analysis. Just...special.

Like, for example, a bloodlust thingy. Every time you kill an enemy, your bloodlust is sated, and this is shown by a brief resistance aura and restoring some of your shields. I thought that up in like 15 seconds, I'm sure someone could come up with something awesome for zerker and for all classes.

Lifesteal could be way, way overpowering or so small it wouldn't matter. It would have to scale to the zerkers level and gear as well, which would make it even harder.

The main thing about solo zerk is that once the enemies are dead, you have to be healed. Zerkers don't have the elec for a high regen shield. If you just gave it to them for free, they would be pretty insanely powerful.

Perhaps if they had some kind of mega shield charger that was zerker only. We're talking huge shield regen, extremely elec efficient, but with some kind of penalty that prevents them from using it effectively in comat, like -100% damage, -100% rof, -20% damage resist, -20% speed while it's active.

So now a zerker could clear a dg level, use the charger to heal themselves, then turn it off and go on to the next level, being time efficient and more independant.

Lifesteal could be way, way overpowering or so small it wouldn't matter. It would have to scale to the zerkers level and gear as well, which would make it even harder.

I'll put out some raw stats here from my personal setups just to show you what I mean is the current issue. This is with added support based on how I play in squads.

Berserker:

With every gear possible moded for the best outcome.

40 138 DPS with Mad Thoraxes, powering easily.
I take 313 631 Hostility/second.

With no moded gear at all.

35 365 DPS with Mad Thoraxes, 75% powering only.
I take 133 460 Hostility/second.

Sniper:

With no moded gear at all for any added DPS or powerability.

43 750 DPS with Mad Thoraxes at Sniper Analysis 0, powering with a large margin.
I take 55 807 Hostility/second.

114 171 DPS with Mad Thoraxes at Sniper Analysis 50%, powering with somewhat margin.
I take 142 713 Hostility/second.

237 280 DPS with Mad Thoraxes at Sniper Analysis 100%, slightly breaking my regen.
I take 296 600 Hostility/second.

tl:drstats/information

With a T21 high end sniper and berserker with no moded gear, the sniper will easily take hostility from the berserker after firing for more than 5 minutes at the same target! The only way I've found yet to prevent this is by giving the berserker the best moded gear possible on all possessions, and it should not be this way!

Why not have lifesteal be based on the shields of the enemy you kill? That was it's automatically balanced to level and everything, it will just work.