Rogue: My favorite character, though she has lost something that made her great to me. I feel like they are trying to hard to make her interesting, let her completely grow up, not be so obsessed with love, and maybe take some time off from the X-Men or something. She also needs to regain super-strength at least. It was ridiculous to remove it, considering her DNA / physiology was changed to have Kree mixed in. After all this time, it was dumb to just say "poof its gone".
Storm: Great character, should probably retire since she isn't doing much theses days.
Jean Grey: I love the character, but sometimes she just isn't written well. When she comes back it needs to be done extremely carefully.
Psylocke: Awesome character, glad they finally started using her correctly. They need to stay away from the whole body swap thing, either combine the bodies or just avoid it all together.
Emma Frost: Great character. Hate that they retconned her being placed in a mental institution origin from Gen X. Also...she isn't going to betray the X-Men, stop talking about it, and actually have her do something instead of standing next to Cyclops and making quips all the time (even infiltrating SHIELD with Danger was boring and she didn't do much). There is a reason she is now a regular X-Man...show people why that is once in a while.
Kitty Pryde: Meh, I understand why people like her, was never my thing.
X-23: I feel she is only written well by certain writers, I like her, but not in every story. Also wish people would stop sexualizing her, the character seems devoid of most feelings, though she is growing, I don't think she is mature enough for that yet.
Dazzler: Great character, but writers use her as a goofball too much. Take her off the team and let her do cameos or actually do something tangible with her.
Rachel Grey: Meh. She isn't Jean, it has been her problem since day one.
Hope: Dis-Like, I hope Jean shows her whats up one day.
Jubilee: Stuck in the past as a teen, now permanently as a Vampire, when all of her other teammates have matured. It's a shame, esp since she could be awesome
Polaris: I love Polaris when she isn't written like a crazy psycho...Can't wait to see her in X-Factor and actually get some decent characterization in. I hope she gets along with Monet.
Magik: She is a great, diverse character, kinda bored with her lately though since all she does is hang with Colossus and teleport everyone.