Less discussed is the first Maria... She was pleasant enough, but a little stiff with the kids. She probably would have loosened up with more screentime, but it ultimately made sense for Maria to be more of a young adult role, and Sonia was, of course, the perfect choice.
Arguably worse than any of the lesser Gordons was Miguel in season 2. That guy was incredibly awkward. I remember reading a quote from Jon Stone somewhere that their Spanish language efforts in season 2 were worse than doing nothing.
I don't think any of the characters from season 3 who lasted only a year were that bad.