Hmm I think tails, wings, gills, and asexual reproduction would be useful. Sonar might be nice....hmmm we don't have the best hearing, vision, etc. either. Hands instead of feet or at least thumbs on our feet wouldn't be bad. Having paralyzing venom could be useful. Oh yeah being able to regenerate (and possibly willingly detach) limbs would be awesome.
Assuming we evolved from apes, the only feasible things we have changed is lost our tails, loss our hair, nose, face structure, we've managed to stand upright.. so i doubt we might have wings, gills, asexual reproduction(plants??)..
Would be nice to have those, but we would need DNA from different animals.