I've spent a lot of time with Mu true enough, but I don't think even with her have I ever been so quickly attracted by a new character before. Perhaps thats why I have a lack of sadness at the prospect that my girl may or may not make a return in some form. I'm okay because I feel like something new is calling. New game is what we wanted and it's what we got!
I agree though, this is just the first PV and chances are other characters will show before this is done. Nu is obviously hinted at but not shown, so I have no reason to doubt Nu/Lambda's style will be in this game. So I doubt they have shown everything they have to offer just yet.
God all of my hype for this.