Shotguns, SMGs and Pistols are all basically useless in PvP. Shotguns don't have AP shells, SMGs are too weak and Pistols are not rapid-fire. Then you look at Big Guns and you've got Miniguns with JHP and AP ammo, Rocket Launchers with Normal and AP Rockets and Flamers with Mk1 and Mk2 Fuel. Big Guns do not need to be nerfed, Small Guns need to be improved.
The Pancor Jackhammer was a beast of a weapon in Tactics and now you see it in FOnline, it's basically worthless. We need Fallout Tactics ammo types for Shotguns, at least.

- Slugs

- Flechette

- Rubber

- EMP

- 12 Gauge
This is why Small Guns rocked so much ass in Fallout Tactics, because of the amount of ammo types, they were balanced and had more variety than Big Guns and Energy Weapons. And Tactics had multiplayer mode, this should be enough to tell you something.
And if the devs are afraid of using Tactics graphics, it's as easy as recolouring this:
