Here's what I wouldve done:
1. I wouldve gotten a writer who knows drama and character to revise whatever simon and kinberg wrote
2. The movie would be 2 hours and 30 minutes or so. If you're gonna close the X-Men franchise, things need to be big.
3. Instead of dying, we never truly know what happens to Cyclops. In the final battle, Cyclops returns.
4. Since Fox are dirty ****es who feel the need to shove logan into everything, most of the film would focus on logan and jean. However, i'd get across the point that logan really cant save jean, and that the only ones who could are dead or believed dead.
5. I'd drop Arclight and Quill, and Bring in Gambit. The fans have suffered enough. Multiple Man would be a spy for Xavier, since he is a good guy in the comics.
6. Storm would get a bigger role as acting leader of the team. Logan dosent need to be leader, period.
7. When Cyclops returns in the final battle, either three things would happen: Cyclops and Jean die in a massive optic blast, Cyke kills Jean in a massive optic blast, or since realizing that Jean cant control her powers, Scott cures Jean. Either way, Scott takes over as headmaster of the school.
8. Deaths: Xavier, Magneto, Mystique, and Pyro
9. The Sentinels would appear half way through the final battle, to show us the **** has hit the fan.
10. The end of the film would set up the new franchise and villains. Either Sinister, the Hellfire Club, or Apocolypse would appear.