Found this on SRK, originally posted by Laban. It's a tier list by Mari, a high level KOF '02:UM player from Japan:
It's not a bad list. My opinions have changed a lot since I posted my own months back and this one is closer to how I view things now. I would put Benimaru back into ultra top tier, and maybe give Robert and Kensou a bit of a raise, but otherwise it looks alright. Finally a list that puts King where she belongs. I also like that EX Iori is high, though he shouldn't be #1. He isn't "inferIori," he's "versatilIori."
My own list nowadays would be something like:
A+: Benimaru, Mr. Karate, EX Kyo, Kyo
A: Iori/EX Iori, Saiki, Shen, Kensou, King, Duo Lon
A-: Robert, Andy, K', Takuma, Kim, Billy, Leona, Yuri, Joe, Athena, Hwa Jai, Kula, Mai, Vice, Clark
B+: Ash, Terry, Elizabeth, Daimon, Ralf, Chin, Mature, Raiden, Maxima
Some of the lower tiers are probably only there because they're under-represented. My opinion will probably change again in another 3 months.