Going from recent tournament results, and in general how the game has progressed since the last tier list, I'd like to propose:
A+: Mr. Karate, EX Kyo, Saiki, Kyo, Iori, Benimaru, EX Iori
A: Clark, Goro, Shen, Yuri, K', Hwa Jai, Kensou, Robert
B+: Andy, Ryo, King, Ralf, Kula, Takuma, Chin, Billy
B: Kim, Duo Lon, Ash, Mature, Vice, Elisabeth, Raiden, Maxima, Leona, Mai, Athena, Joe
B-: Terry