She is actually a lot... less... malicious and antagonistic... although you wouldn't really know it to look at her. Or really just sort of broadly antagonistic rather than specifically antagonistic. She is unpleasant to a lot of people and makes a few people cry versus ruining someone's life specifically.

She is also more independent! Erika in canon is just a piece in the game, which means almost everything she does is planned and directed to some extent by her master Bernkastel. Though this also has the effect of making her not care a whole lot about acting the way the personae want her to in games and stuff. |D

How is Madoka currently doing with her castmates? (I am canon-familiar but I don't really stalk any of them much. :B)