If you want violence, the Iron Age sourcebook is a good tool to have. It has lists of hundreds of different guns, even though all of them still do the same damage as the usual light pistol, heavy pistol, shotgun, etc.
The bonus is, in really violent games with guns, players want to specify what kind of gun they are using. Players don't want to wield a heavy pistol, they want to wield an Israeli Arms .50 coliber Desert Eagle with chrome plating and a pearl handle with a dragon inscribed on it.
And if you want REAL violence, just make the effect of punching a guy in the head with superstrength do what a punch should do coming from a guy who can lift a subway car. Ewwwwww.