The real reason EA has been slow to release female characters is that most of them (like 90%) are unvoiced characters due to the fact most women in the show are voiced by Tress MacNeille and Pamela Hayden, who aren't counted as main cast and EA won't spend the extra money to get the rights or whatever. This has been discussed on here before. Only the Bouviers and Lisa are voiced off the top of my head. I think most of the time they'd rather release a voiced character rather than unvoiced, which sadly means they release more males than females. Probably because people (rightly) moan about the unvoiced characters.
Hopefully the fact they got Matt Groening is a sign that things might change and they might get the supporting actors' voices. Although I suspect as creator of the show Matt waived the fees or something.....