It was recently reported that Tim Miller and Fox are actively developing a Kitty Pryde film. Disney's acquisition of Fox is clearly not keeping Fox or Tim Miller from developing projects like this one, though it does mean that this may not ultimately hit the big screen. That being said, Fox's X-Men franchise would benefit greatly from a Kitty Pryde film. Regardless of whether Disney decides to give the X-Men a reboot, it'd be wise to at least consider giving this film the mouse stamp of approval.
The X-Men franchise has released a myriad of successful films over the last two decades, most recently Logan, X-Men: Days of Future Past and, of course, Tim Miller's Deadpool.
Hugh Jackman owes much of his fame to the role of Wolverine, a character who has proved to be immensely popular among film and comic book fans alike. That led to spinoffs X-Men Origins: Wolverine and The Wolverine, which while underwhelming from a creative viewpoint, got people calling for more solo films, and in turn led (partially) to the highly successful Deadpool.
Clearly, focusing heavily on Wolverine paid off. But in doing so, other characters were kept from expanding into well developed, memorable characters. Fox allowed a number of powerful, intriguing characters like Jean Grey, Storm and Rogue to fade into the background. Just look at Storm's appearance in X-Men: Days of Future Past, in which her role was reduced to a few fights and one underwhelming death scene.
We can't ignore the fact that recent entries have allowed Mystique to develop more as a character than anyone would have ever thought, were they to judge from the original three films. Rebecca Romijn was able to give the character a bit of mystery along with her obvious sex appeal, but Jennifer Lawrence -- with her star power -- was able to give the character much needed depth. Because of this, Mystique has risen in popularity as a character, something that really hasn't happened for Fox's other female characters. Even so, it's unlikely we'll see a Mystique spinoff film in the near future.
The X-Men films need to start focusing on someone new (read: someone other than Wolverine or Deadpool), and the best way to do that would be through a solo film. That's what's so exciting about this Kitty Pryde project. But in Fox's X-Men universe, Shadowcat has never been more than just a supporting character, so why should she get a spinoff film?