Tried it out, and it works all fine and dandy! Voice clips are missing plus the metal cap still uses Toad's model, but I'm sure they'll be fixed in a future update.
Apologies if this sounds reeeally nit-picky of me, but I feel that the feet are too far back on the model, it looks a bit unnatural from the side. Also maybe the torso portion could be a bit wider on the side. But other than that, everything else seems to be okie-dokie! Good job!
BTW if you're looking at potential costumes for the future, might I suggest Captain Goomba and Private Goomp from the Mario & Luigi series? (I'd imagine the former would be the easiest since you just need to attach a flagpole to the top of his head).