Like many older neopets, there are not too many colours left. Tyrannian or Zombie could be interesting if done well. Chocolate might be interesting if done well, as might Jelly. Ice tends to be more iffy, but can be nice. Biscuit is usually half-way decent while Sponge has not been done in some time (and lost a lot after the revamp). Invisible is okay, if lazy. Custard and Snot are Custard and Snot.
Thoughts, hopes, desires?
Faster than a speeding cheeseburger, but not by much.
I'd really want to see Tyrannian, even though I don't play anymore. I still love Gelerts. x3
As for another colour, I'm guessing Chocolate or Invisible.
I always guess one lab colour and one attainable one, so I'll call... Zombie and Chocolate. A Tyrannian Gelert would probably suffer from looking too much like the Lupe, but Zombie is plausible and could be played with quite freely, and a Chocolate one might be quite fun-- they have those long ears that could be drizzled, and a tummy that would look nice in white chocolate.
and Disco 
