The following is a discussion / suggestions based on the current design layout of GR:B (not a discussion as to should it work this way, just how it currently works).
We went through a shotguns only raid the other night. Doable but boy was it painful. It shows the limitations of the shotgun class in this game where they do not seem viable beyond gimmicky type runs. Both from lack of suppression, lack of range and the only real viable shotgun is the BOSG12. Primarily because it shoots a slug and not buck and has decent range. Where the shotguns show their biggest draw is against murmurs and drones in general. They are supposed to be the defacto drone killer but you're better off with a Koblin or a stoner with +drones rolls. Even the flycatcher is better.
They aren't included in this cursory analysis because the shotguns are that bad and really need to be looked at from a play-ability stand point.
So onto the DPS / DPM analysis. It's obvious from a pure stats standpoint there is a leader in all the weapons and that is the Koblin / Stoner combo. Of the ones I looked at there are stat deficiencies in normalizing choice of weapons that can either be addressed by upping round damage or firing rate. I know we are probably far away from this game going into balancing mode but for those of you raiding, this can be handy breakdown to assist in speed run optimization.