Thalaron mine would be cool. Worfzooka... oh my, yes, we need that. I have the perfect away team boff on my crew in mind for such a weapon. Operable mortar sounds interesting. How about one of those under-the-barrel small grenade launchers? Might be a fun omega force ground shiny.
I can sort of see that now, full auto rifle but with the aoe replaced by the rifled grenade.
I'll sell you some weapons from New Romulus. Never fired, only dropped once.