If Mai did not have EX Fan she would still be an extremely strong character, her movespeed and buttons are great and she has some of the best corner carry in the game and THE best throw loop in the game, as well as SA1 also buffing her other moves. Her only weakness would be that her DP is only "okay" as an antiair (ie it whiffs sometimes) but considering how many characters lack an air invuln move let alone a DP that's not even that big of an issue. She also has an incredibly strong momentum halting divekick with almost no hurtbox for some reason.
EX Fan and charged fan in general makes her MUGEN tier busted and it and her other tools need a complete rework.