Fans who were hoping to get clarity from Bryan Singer's X-Men: Days of Future Past might find themselves walking away a bit disappointed. Aside from clarifying a few things here or there, like Xavier getting crippled in 1962 and shown walking again in later years, not a whole lot was explained. Even more frustrating, for fans who were hoping to finally have a coherent X-Men universe, is that the film creates a lot more questions to add to the backlog of already puzzling quandaries. It should go without saying, but looking into those questions will necessarily require spoilers, so consider yourself warned.
8. So is Jean gonna go Dark Phoenix again, or did that get taken care of somehow?
The most noticeable change to the timeline when Wolverine wakes up in a new and improved future is that Jean Grey and Scott Summers aren't dead anymore... then again I was never all that sure that Scott was really dead, since we never saw his body, but that's a moot point now. Scott's "sorta-kinda death" has been undone and Jean's "very definitive death" has too.
While that's very good news, it's also potentially disturbing news because it leaves one wondering if Jean is a ticking time bomb of unrelenting rage waiting to go off like she did in X-Men: The Last Stand. Did that already happen in this timeline? Did young Xavier get enough info from reading future Logan's mind to realize what a big problem that was gonna be and figure out a way to head it off at the pass? Has her death at Alkali Lake been undone too, meaning that she's still got a resurrection as a power mad psycho in her potential future?
Chances of an Answer: Pretty Likely.
With the franchise reset to 1973, it seems very likely that this question will eventually get explored. If it's not addressed in the upcoming X-Men: Apocalypse, there will be plenty of other chances to explore the issue.
7. How the hell did Kitty figure out she can send other peoples minds back in time?
Due to a lack of time machines in the X-Men movie universe, a more unconventional plot device is needed to get the ball rolling on changing history. Kitty Pryde is revealed to have the ability to send a person's mind backwards in time so they can alert the team of impending Sentinel attacks. This requires a bit of disbelief-suspending above and beyond what is normally necessary for a movie about people who have super powers. Is it too incredibly difficult to think that someone who has the ability to put a person out of phase with 3 dimensional objects could put their mind out of phase with 4 dimensional time? Maybe.
The question more puzzling, though, than how Kitty can shift someone's mind through time, is how she came by the knowledge that she can do it at all. Her basic ability to walk through walls is an easy one to stumble onto. It's something that could just accidentally happen to her. Figuring out that she can shift a person's consciousness seems incredibly unlikely to happen accidentally. It's even less plausible that she would have figured it out by giving it a try just for the hell of it.
Chances of an Answer: Slim.
There might be a deleted or extended scene coming up the pike that addresses this. Lacking that, a future movie could show the new timeline's Kitty figure this ability out on her own. Both possibilities seem remote though. Kitty's new power seems to be the best route that Singer and his colleagues could find for getting the time travel stuff off the ground without a need for complications, so it doesn't seem like something that will get expanded on or even mentioned again.
6. Why does Trask's martyrdom take over 30 years to get the Sentinel Program up and running?
Early on in the movie it's explained by future Xavier that the rise of Sentinels taking over everything was set in motion by Mystique killing Bolivar Trask and giving the anti-mutant crowd a martyr to rally around. This idea makes sense if you don't linger too long on it. An important industrialist who warned everyone who would listen about the dangers of mutants being proved right via his own murder seems like the perfect thing to turn the tide of public opinion against mutants.
The problem that becomes clear with just a little bit of extra contemplation is, why wasn't this turning of the tide more immediate? All of the post-1973 movies show practically no indication that giant robots hunting mutants was ever a thing.The only hint of Sentinels up till now was a brief glimpse of one in a Danger Room simulation in the third movie. That doesn't make clear if Sentinels are a present day concern, or a concept in talks that Xavier wants his students to be prepared for just in case. The lack of any giant robots at Alcatraz when Magneto and his army of mutants attack Worthington Labs makes the latter scenario seem more likely than the former. For being such a rally point for the anti-mutant crowd, Trask's memory sure failed to get much rallying done.
Chances of an Answer: Unlikely.
This is another case where there might be some bonus material out there that sheds light on the matter. Short of that there's little chance that any sequels will deal with the matter now that it's been written out of history.
5. In the original timeline, how did Mystique escape from Trask Industries?
The other big contributing factor to the original timeline getting all dark and gloomy is Mystique getting captured by Trask's goons after successfully killing him. Study of her physiology eventually led to the creation of the superior Sentinels seen in the future that can adapt to and mimic mutant powers. Like the martyrdom of Trask, this is a concept that only makes sense if approached with minimal curiosity.
Once the situation is looked at with more intense scrutiny, a big question becomes obvious. How did Raven Darkholme escape the clutches of Trask Industries and end up with Magneto's newer, smaller brotherhood in the first movie? The security around her must have been tight as hell. Any rescue attempt should surely have been undertaken by people that had some idea of how valuable the knowledge of her biology was. So why didn't her rescue also involve the destruction of that data?
Chances of an Answer: Unlikely.
Once again, the only chance at getting more info lies in whatever bonus material ends up on DVD and Blu-ray. Whatever sequence of events resulted in Mystique being freed from Trask Industries is part of a timeline that has been nullified. It'd be nice to imagine that Magneto eventually rescued her, but that only leads to a bigger question...