This game is so explored and developed that we have many great and famous Japanese players for every character, except for Elena and Sean.
Sure there are high level Elena players such as Sei and Ikego, but they are not at a ‘superstar level’ like the players below.
For the rest of the cast, there are already AT LEAST ONE superstar-tier player for each character:
Alex: Genki, KSK
Chun Li: MOV, Nuki
Dudley: Kokujin, Fujiwara
Gouki: Yuki Otoko
Hugo: YSB, Hayao
Ibuki: Aruka, Higa
Ken: Deshiken, Daigo
Makoto: Boss, J
Necro: Sugiyama, PinoAB7
Q: TM, Kuroda
Yun: Ochibi, Yakkun
Elena: Still awaiting a specialist
Sean: Still awaiting a specialist
Most of the listed above have done some great feats like winning big tournaments.
We are still awaiting someone who would play and stick to Elena and do what Pierrot has done with Remy, and what Thanatos has done to Oro… what Sugiyama has done to Necro, etc.
Some players who main Sean eventually give in and just switch over to Ryu…
Even if the Sean player rarely gets wins over the other top players, he can still become like what Yamazaki is.