I don't know if this is old or not, but I didn't see any topics on it. This is a video overview of the skills and characters in the game: http://www.youtube.com/watch?v=i4jXNB-gs6w this video makes it clear that I'm using Maya second, after Salvador. She looks like a lot of fun for when I play co-op.
I have Dysarthria. It's a Speech problem. Your question is answered now.