I've asked these questions countless times, especially during Days of Future Past when things came full circle. I finally re-watched the first three XM movies and had even MORE questions.
Like
In The Last Stand, Wolverine and Beast managed to trick Magneto and stab him with The Cure, right? So while Jean was going all apeshyt and fukking everyone up, why didn't Wolverine think to just sneak her with the Cure?
There is, of course, the very strong possibility of the syringe getting destroyed in the process. But dude didn't even try. And I'm not too worried about that. Of course they had to make the film dramatic. It would have been too easy if they could have cured Jean just like that and there's also the case of the Cure possibly being faulty due to Magneto getting his powers back although I like to believe that Magneto is one bad ass mf and can't let a stinking antidote stop him.
My BIGGEST question of all time is how the fukk did Charles come back to life?
No one ever explained themselves and I thought Days of Future Past would tell us a little something since Charles showed up at the end of the last Wolverine movie but no. They just brushed passed it like we wouldn't notice. 
My mother has a theory that Charles faked his death, which is why he smiled before Jean disintegrated his ass. But I'm not so sure.
Jean killed a few people in the matter of which Charles died and he was dead for sure. Unless he had his own version of The Phoenix and was reborn? fukk I don't know! 
And with them managing to change history, purging the idea of the Sentinels, will that stop Jean from turning into the Phoenix
Other moderate questions are as followed:
Why were Storm and Cyclops, some of the most powerful mutants in the game constantly useless and getting their ass handed to them throughout the franchise?
Why they didn't bring Gambit back?
Where the fukk did Night Crawler go, he was useful af.
Why was Rogue's boyfriend lowkey a dirty down two-timing dog?
Is Mystique immortal?
Who do you ship Wolverine with?
Like
In The Last Stand, Wolverine and Beast managed to trick Magneto and stab him with The Cure, right? So while Jean was going all apeshyt and fukking everyone up, why didn't Wolverine think to just sneak her with the Cure?
My BIGGEST question of all time is how the fukk did Charles come back to life?
No one ever explained themselves and I thought Days of Future Past would tell us a little something since Charles showed up at the end of the last Wolverine movie but no. They just brushed passed it like we wouldn't notice. My mother has a theory that Charles faked his death, which is why he smiled before Jean disintegrated his ass. But I'm not so sure.
Jean killed a few people in the matter of which Charles died and he was dead for sure. Unless he had his own version of The Phoenix and was reborn? fukk I don't know! And with them managing to change history, purging the idea of the Sentinels, will that stop Jean from turning into the Phoenix
Other moderate questions are as followed:
Why were Storm and Cyclops, some of the most powerful mutants in the game constantly useless and getting their ass handed to them throughout the franchise?
Why they didn't bring Gambit back?
Where the fukk did Night Crawler go, he was useful af.Why was Rogue's boyfriend lowkey a dirty down two-timing dog?
Is Mystique immortal?
Who do you ship Wolverine with?
hopefully Apocalypse is dope cuz dofp was meh af.