The BFP - The Big Fucking Pistol
Because AoMr needs a use for plasma cells and a Big Fucking Pistol is more fun than a Plasma Pistol.
Stats, I dunno, maybe something like:
Dam:5d5
Spd:1.0
Rel:2.0
Explosions and stuff as the old BFG, hits where you aim and explosions hit everything and stuff like that.
Clip: 80/20 per shot
Basically, with a bulk mod you get 5 shots which should be enough to kill everything(at least with SoAGx3), the 4 shots without bulk isn't guaranteed to kill viles if my math is correct. Kind of like the BFG, the normal two shots you get doesn't usually kill everything but three shots you get with a bulk mod kind of does guarantee kills.
Also,
Drilling Tool [...] would be useful for storming the wall in AoMr/Sh/B... just for the e-peen or something?
At least for AoSh I'm pretty sure the Plasma Shotgun shoots through walls.(probably because of plasma piercing armour)