Been a minute. So this has probably been suggested before but having seen this implemented in some other games... I thought I'd bring it up.
I admit I'd rather see this in the ex slot but it effects damage so they're going to force you to replace something on your build...
My solution is a ricochet mod. Effects only semi auto and automatic weapons. Ideally sidearm but preferably one for primary as well. With the exception of shotgun primaries and sidearms for reasons which will become clear.
My suggestion is that a ricochet mod with 20/35/55% chance per projectile to ricochet off of 2/4/6 targets within 5/8/10 meters. Headsets have 100% chance to ricochet and 33% chance per target to land as a headshot and stagger.
Disables punch through, obviously.
Even maybe limiting it to semi auto weapons because there are certain weapons that it might be a little intense on. But semi auto, especially precision weapons, need help. And unless we're going to make them one shot most targets, making up for poor crowd control in bodies on the floor, having add on crowd control at a price might help.
Being honest most of the meta weapons don't do the best per target damage, but they deal it over a wide area. These precision weapons often deal more target damage when optimized but the lack of aoe just causes them to fall flat. Losing a damage mod to gain area of effect may be worth it in some cases.
Anyway just a thought.
On that.. aside de keeps trying to think of ways to make puncture and impact work, what if puncture had innate punch through and impact had innate ricochet (the heavy impact causes it to bounce off)... just a thought..