Add a supression system that slightly blurs your camera as someone shoots towards you. Lets say a shot passes by you in a radius of 0.3 meters (idk if its a lot or not, just using it as an example), your camera blurs a little, if more shots pass by you, it gets blurier (kind of like Hell Let Loose).
It would be a buff for Support that can keep firing lots of rounds. Even read on another suggestion post about giving xp for supression.
Make it so that caliber affects how blurry it gets, a sniper round will blur more than a pistol round.
I can see how many may dislike this since it will slow down the pace of the game, but i think it could be a fun feature depending on how its implemented.