The old zafara is badly drawn, but I prefer its design (body like an asian dragon) to the current one (body like a...kangaroo?); however, seeing as how they're quite popular as is, it'd probably be best to do just a redraw, not a revamp, so as not to upset anyone.
The main changes in the "new" Neopets drawing style are more variation of line, better and more detailed shading, and less stiffness...I'd say that would help the zafara a lot.
Personally I want a redraw of the shoyru! I actually painted mine halloween specifically because the basic colors are awful. More recent shoyru colors like faerie, pirate, halloween, maraquan, and darigan are fine, but the basic shoyru (the ones with fill-in colors) could use a little update. No redesign, though, please! Shoyrus are the most popular pet for a reason.
Besides that, gelert, elephante, peophin, flotsam, jetsam, blumaroo, chia, zafara all could be fixed up a bit. Especially gelerts because I own one and want him to look more current.
Also, jubjubs deserve a re-revamp. :\ When they decided to revamp the jubjub I thought it would be revamped like this:

I think this is very cute!
But this is how it was actually revamped:
I don't like it very much now.