An idea I've had for a live action X-Men series:
Season one: We're introduced to the Xavier school for gifted youngsters, a private school in Westchester for the "especially gifted". The student body is small, roughly ten students in all. There is one teacher, who serves as the headmaster. Professor Charles Xavier, a billionaire scientist and philanthropist, and a major political voice in the movements for civil rights. Charles is also a mutant born with vast telepathic abilities, and quite possibly is one of the most powerful mutants on Earth. All of his students were born with genetic mutations that give them superhuman abilities as well. He has brought them together to help them learn how to use their abilities responsibly. The older students who choose are trained in how to use their abilities to help others in slightly more active ways (learning how to be superheroes, basically).
The main cast of characters are Scott Summers, Warren Worthington, Jean Grey, Hank McCoy, and Bobby Drake. The other students would be Sam Guthrie, Daniel Moonstar, Doug Ramsey, Xi'an Coy Manh, and Amara Aquifla. However, their's would be small roles in season one and they would not technically be members of the X-Men. Much of the first season would involve Xavier and the older students tracking down and recruiting other mutants with powers. Throughout the first season, they would meet with and confront Magneto and his brotherhood, sometimes when both sides want to recruit the same mutant teenager, other times when the X-Men have come to stop Magneto from doing something evil. The season finale would culminate with Magneto leading a full scale terrorist attack on Washington DC, and the X-Men coming to stop him.
The second season would introduce Wolverine as a mutant Xavier found in the woods of upstate New York. He would eventually become the guy in charge of the danger room sessions. In this season, they would flesh out the other students and recruits from season one as characters, and most of the more character centric episodes would revolve around them. The main arc of the season would involve the government's Weapon X and Sentinel programs. The season finale would culminate with the X-Men fighting Weapon X forces and some Sentinels. The Sentinels wouldn't be giant mech sized. More around 10 to 12 feet.
The third season would have the Cyclops/Wolverine/Jean Grey love triangle as a major sub plot. The main plot would revolve around Xavier discovering that the school's benefactors, the Hellfire club, have been using him and his students to further their own purposes. The season finale would involve the Hellfire club kidnaping Xavier and Jean and using their psychic abilities to try and awaken what they believe to be an ancient Egyptian demon to use in their bid for power.
The fourth season would have Wolverine searching for clues about his past as a major sub plot. By this time, the school has grown to over 30 students and other teachers such as Moira McTagart and Sean Cassidy have come to help staff the school. The school is now known to be one for super powered mutants, and has become a target for both bigotry and praise by the public. By now, Jean, Warren, and Scott have graduated the high school level and are taking college courses while helping out the staff at the school. The X-Men team has grown to include Nightcrawler, Kitty Pryde, Colossus, Storm, Gambit, and Rogue. Also, another sub plot would involve Rogue becoming a student at the school and adjusting to the school. The main plot would involve Reverend William Stryker leading his hate campaign against the mutants of the world, both powered and otherwise, with the help of former government scientist Bolivar Trask. The season finale would culminate with Stryker leading a campaign to exterminate the mutant impurity.
The fifth season would see a return of Magneto after he escapes from a maximum security government facility and goes about to free his other captive Brotherhood members. We would also see Emma Frost of the Hellfire Club looking to complete the ritual the club started at the end of season three. Partway through the season, this would result in her awakening Apocalypse, a vastly powerful mutant and barbarian warlord from Ancient Egypt who has been trapped in a form of cryogenic stasis for several centuries. The main arc of the season would be Apocalypse trying to conquer the world, with the X-Men and the Brotherhood teaming up together to stop him.
The sixth and final season would be an all out war on humanity led by the Brotherhood. By this time, Logan has unveiled the mysteries of his past, Jean and Scott are getting married, and Xavier has begun a shaky working relationship with the United States government. The season finale would be a final battle between the X-Men and the Brotherhood, as the brotherhood declares all out war on humanity.