It's official: Mickey now has Fox...

The X-Men and the Fantastic Four are home now. The cool thing is they are home... the scary part is fitting them in the MCU... Fantastic Four can be added in a post Avengers world with a few tweaks. (We could use the Negative zone  as a source for their powers.)
Like say, have a flashback of a younger Reed and Von Doom working with Pym on an experiment to enter the Quantum Realm WITHOUT shrinking. The outcome has Pym shitting down the project thanks to Reed noticing errors in Von Doom's calculations. Doom's bruised ego makes him swear revenge on Pym and Richards. Years later both Richards (now working on the Baxter Bldg. For Franklin Storm) and Von Doom (now crown Prince of Latveria) attempt their Quantum realm experiment.
Richards and his crew, Become the F4 we know. (This being told via narration and maybe a few flashbacks to save time.)

Von Doom on the other hand actually reached the Quantum Realm, but his portal was unstable and it exploded... creating a minuscule scar on his face... (and tossing him through time and Space.) With a mildly temporarily displaced Von Doom, him getting caught up with the age of heroes, he decides to become a Hero and save Latveria, then the world and becomes Doctor Doom.

For the X-Men, I still stand by my, they've been around for some time, but not available for Fury.

For something even scarier, casting the characters... especially Doom, Wolverine, Xavier, Magneto... Hopefully they won't stray from the source material... also:
Do not pick Kit Harrington as wolverine!!!
I don't want Bitchface Jon Snow ruining X-Men for me.
Also, if The MCU X-Men are going to tackle the Phoenix Saga.. add Space and at least more than 1 movie...
Holy crap, thw next Thanos could be... Onslaught!