Hey neat idea! It'd be really cool if you could animate his mouth while he's talking, too. It would be simple to do, just animate his lower jaw relative to the rest of him. Two simply movable meshes on a hinge... In cartoons (not the recent ones), the villain would appear more menacing/scary by having very simplistic-like animations, so that would be an advantage here, with your style.
Although to sync that up (jaw animation with speech) would probably be beyond the scope of FPS Creator - well maybe not, you'd have to manually sync it up with a script to accompany certain speech sound files. It would take a little time, but it would be really cool! If he has a long dialog somewhere, rather than doing it in one shot, have a number of sentences played in sequence. That way, they can each be re-used later and in other contexts. In other words, just do single sentences at a time, that puts the work into byte-sized chunks (not pun intended

).
I'm thinking it might be good to have a little variety though, like a trashcan head would have a different top than a trashcan, and vice versa. I suppose that's possible, but junkyards usually have more variety than just the metal trashcans. If someone was going to make a body for himself there, he'd have to use whatever was around.
Another idea I had about your currently pictured dude, you could have him wearing over his top, a stretched (conquered) tire as a diagonal sash, like Warf does:
P.S. You could animate his eyes, too, and have him be able to turn his head. You could make him quite a character!