Since you asked, I'll tell ya the ones that caught my eye (360 version only, Wii users will be ignored).
Sheep Burner Spyro: Are you kidding? Sheep Burner Spyro is terrible in PvP; not average, not good, not great. The Flame Shield doesn't benefit at all, the Daybringer Flame does only 30 damage and is pretty slow, and the Exploding Flameballs are pretty worthless. My Spyro got his ass handed to him several times, he is so much stronger on Blitz Spyro.
Nether Welder: Seriously? Why does everyone like Nether Welder? I find it Ultimately worthless! All it does is make weak exploding ghosts, a longer hold duration, and the lightning gets thicker and longer. It's pretty lame, and my Cynder barely won any fights on that path.
Sandhog: Not broken, he;s not as strong in pvp as everyone says on this path. Razorfin only does 15 damage, so it's not very great. The most important weakness on this path is Master Earth Swimmer. That makes him so fast its very difficult to control, so it's a problem around platforms & obstacles. Also, he'll have to rely too much on Dirt Swimming, he's not so powerful in the surface because his mini sharks & punches do weak damage without Brawler. Should be placed a little lower than S tier.
Telsa Dragon: He's not as weak as everyone says he is. It's definately better than Sea Slime Serpent in PvP, that path is fun but kind of useless. At least the bouncing Lightning and Electric Wave helps, and Telsa Storm helps a bit too.
I made my own personal Tier list.