I was actually thinking a kind of grenade launcher for drudge. It fires radiation grenades really far has like five nades per clip and alt fire could be nade shower it just fires all of them in a spray. Its weakness would be it takes long to reload you put each individual grenade in, and it has like a recoil or something that takes out a chunck of health or has low ammo.
The carbonizer is kinda a flamethrower... But yeah, a true flamethrower (that sets people/stuff/scenery on fire XD) would be nice. Also the game lacks a true human assault rifle (ak-47), strong bullet, fast fire rate, not perfectly accurate. The strike/striker rifle and hive cannon may take its place though.