That'd be an interesting gijinka.
I wouldn't mind exploring another gijinka species as well, specifically ditto. I've always imagined that they wouldn't really be in control of their powers, so they'd be constantly shifting to mirror the world. It'd be really fun to work the personality around that, perhaps even of a slight mirror of those around them, so that they're constantly changing depending on the situation and would slowly morph into their own selves only when there was no one around to (or that they can) mimic. I'd also love to try again with the idea of Que, this time as a Sawsbuck or Gogoat, just because I think that a huge set of bighorn sheep esque horns would tie him together so well
But I do quite like who he is now.
Granted, I don't really have the time nor inspiration to build these ideas, but it's always fun to think about.