N. Tropy has a base Speed of 4, a base Acceleration of 3, and a base Turn of 2. Basically, he's better than Tiny Tiger or Dingodile by 30 percent. In terms of best characters, I believe this is the correct list:
1) N. Tropy
2) Crash Bandicoot/Dr. Neo Cortex/Komodo Joe
3) Tiny Tiger/Dingodile/Papu Papu
4) Pinstripe
5) Polar/Pura
6) Penta Penguin/Ripper Roo
This is not including N. Oxide, who would utterly own each one of these poor souls if he were an unlockable.
If you see me posting, it's because I've been asked to. Which I guess would mean I'm taking requests.