TBH I think what we should have are varied mercenaries that fill niche roles.
Heavy Tank - Minigun/Rocket Launcher
Sniper - Snip Rifle
Assault - Shotgun/Rifle
No Mercenary group would issue only boom guns to the people they hire out, course the mercenaries the gals have access to won't be top tier for good reason.
Mercenary costs are rather high, but tbh it fits in the flavor of how over priced illegal goods are. While I'd like it if the merc were like the lightning banger who can pick up and drop items, but when you have a govt/team issued item you generally hold on to it. Maybe the merc is mentally incapable of picking up items due to training implants.