I'm in Act 3 with her, and at least if you play as Durge, I think it makes total sense with her character that she is only available for an evil group. I don't want to spoil anything, but afaik as I can tell you can't lead her into a good/bad direction like with origin characters (if I didn't unintentionally lock her into the evil road at some point, or there is a surprise ending).
She isn't a "mindless butcher" kind of evil, but what she wants is just not possible to do with a good group in my view. If you go down the evil road though, she is a great adviser and cheerleader. : )
