Well I have an interesting idea for what I would be. If it's possible I would want to be the offspring of a Q and a changeling. I'd get the best of both worlds. We know that two q can have a kid but can a changeling mate with another species?
ok if not then
1. changeling
2. Q
3. whatever race Nealix (misspelled prob.) from Voyager is, he has cool hair and skin