Disney has a decent lineup of Fox/Marvel movies to choose from.
After all, it’s far from the only movie the company acquired in the merger.
I personally think X-Men: First Class would’ve been a solid choice.
You have to wonder why Disney decided to lead off with Fantastic Four, an overwhelmingly gloomy and dark superhero movie that is practically the antithesis to the tone Disney and Marvel have crafted for their superhero films, rather than just bury it somewhere deep inside their vault.