Because of the lukewarm reception on Zero in the previous game, the sponsors repeatedly requested the development team to make Igniz handsome:

"Since all our sponsor had to say to us-about 100 times-about Igniz was "make him hot," "make him hot," and "make him hot," we made him, well, a real stud. (LAUGH)
The standards for handsome characters in fighting games for Asian fans are exacting; and there is a tendency for people here to shy away from ugly and comic characters."
Contributed by DrakeVagabond
The inception of May Lee Jinju was at the request of the game's sponsor, Eolith, expressing a desire for a "Korean Athena" character. This request initially asked for an "idol-like visual fighter," which charged over time into what was in the final game. She was named after the person who was in charge of Eolith at the time.
Contributed by DrakeVagabond