I can't explain the dis-like for Rachel, (I don't consider myself a Rachel-hater, there have been times I have been ok with her character.) But over all, she hasn't impressed me.
Maybe it's the mullet. Maybe it's the temporal displacement. Maybe it's the use of the phoenix force. I think it's just something about her over all style, I'm just not attached to the girl, and would probably have her out of a story rather than in it. (of course, my philosphy might just be any panel without Jean is a wasted panel :p )