I liked Angel better as Archangel, myself -- now that being Apocalypse's Horseman has all worn off (yeah, right, that's old Apocie, just planning for the short term) Warren has gone back to being pretty vanilla.
Mister Sinister as a villain would be incredibly, remarkably cool. I could just imagine him and Mystique going at it in a shapeshifter's duel. Probably give the CGI guys nightmares, though.
I love Storm the comic book character, but Halle Berry Storm deserves to go. So bland. Blech.
Conversely, I don't care much about comic book Cyclops, but would love to see movie Cyclops get more screen time.
Cyclops, Colossus, Iceman, & Nightcrawler are who I'd like to see more of.
I'd like to see Psylocke (the Betsy, not the Kwannon), Moonstar, Wolfsbane, Dazzler, mentally-unstable Polaris, Havok, Cannonball, Sunspot...(yes, I started with the New Mutants. #42, to be exact).
Villainwise...The Hellfire Club. And Sinister.
Cheers
Nell.