((I really dislike when people determine something and don't explain themselves. I disagree with the w0lv3rine, in the animated series, She was in love with Gambit. So, she wasn't gay in that since of the word. If you are referring to powers, her's were more of a curse than a blessing. I felt sorry for her.
In my opinion Wolverine and Apocalypse was the cheapest ones. One of which, if you are going by the movie, could heal from a head shot in less than five minutes and with out any permanent damage. The only way I can remotely think of killing the other one would be destroy the modern X-men time-line, and going back in time and kill his parents, but that would be impossible, for even if you could time-travel, You wouldn't know who to kill they never cause Marvel never stated who his parents are.
I said my peace...
Jean Grey, I would have to say is Raven's character. If she like Psychic powers... Here is Marvel's bio on Jean for you to read if you wish
http://www.marvel.com/universe/Phoenix_(Jean_Grey)My favorite X-men character?
I can't name a single one, but in Alphabetical order here is my top 12.
Angel: It is the wings, nothing more. Hay wings are cool, even after they are replaced with the Adamantium ones.
Beast: Intelligent, Strong, and Fast.
Cable: Badass from a different time.
Forge: The ability to create any mechanical device one wishes.
Gambit: Something has to be said about someone who thinks he can take on Apocalypse alone...
Jean Grey: Same reason for Professor X
Magneto: Peace at any cost, Sound so much like the US military
Nightcrawler: Hi...*Poof*
Professor X: I like the idea of psychic powers.
Rogue: She is the greatest trooper there is. If I was cursed with her powers, I think I would have ate a bullet by now.
Storm: The power of Nature's most powerful storms at your fingertips
Wolverine: Badass from our time. [Hay I said he was cheap, Not that it is totally a bad thing.]))