I'd do it from a pure stance.
The Astonishing X-Men
Original five xmen. The story doesn't have to be some grand scale. It would start with jean grey discovering her powers and arriving at the school. She would then start training with the other xmen as all characters develop. As some of the brotherhood begin to attack government sites, Xavier would then reveal to his students the existence of his former friend, Magneto. He would give them the choice to use their abilities to defend the powerless against those who would abuse it, or to simply go on as a normal citizen. Naturally, the five move to stop members of the brotherhood. The fight is somewhat sloppy, but they drive the bro.hood back. Realizing that they are still rough around the edges, Xavier begins to drill them on team tactics and reveals the sub levels of the mansion, specifically, the danger room. The professor warns them that Magneto is incredibly powerful and is bent on blah blah blah. They train and develop further. When magneto finally makes a play for a top secret gov site that is building mysterious, advanced weapon systems (revealed in eventual sequels to be sentinels), The xmen confront him directly. Obviously they win in the end and are now, " 'bout that life". Professor Xavier, speaking with scott and jean, explains that more and more mutants are popping up and that they need to be ready to help and welcome them to the school. Prof.X asks Jean to begain minor use of cerebro in order to assist him. He reveals to her that she has telepathic abilities that he'd blocked until she would be ready to gain control over them. He lets her decide on whether or not she's ready. Naturally she chooses to on block her abilities and she begins learning how to control her telepathy under the direction of Prof.X. Jean also begins to assisst the prof. in using Cerebro. As they scan for mutants in north america, Jean zeros in north canada to a fierce battle between a two large beasts and a ferocious animal with claws. She only gets brief flashes of rage and slashes. Movie ends: Cast would be mostly unknowns. There would be two xmen outfits. The more traditional look with yellow, would be what they wear while training. When they confront magneto in the climactic battle, they wear oufits that are only navy blue. Cyclops would have his skull cap. All xmen would wear a version of a load bearing vest that has first aid and light supplies. All in all, a pretty practical look that is def NOT black leather. It would look slightly simular to the first class outfits.