Marvel Characters That Should Be in the Marvel Cinematic Universe

A list of personal favorite superheroes I think should be in the MCU.
Some of these have made cameo appearances, but deserve the spotlight for at least one movie.
All of these are possible, seeing as Marvel owns them.
WARNING: Spoilers for all MCU movies ahead, including Infinity War.
This list is a non-votable list and the content of the list reflects the opinion of its author.

The Top Ten

1 X-Men

The X-men are a group of mutants led by Professor X. Their appearance is long overdue, and with the Disney/Fox merger deal coming soon, it should happen.

2 The Fantastic Four (1994)

The Fantastic Four is a group of way over four superheroes, also overdue in the Marvel universe. Similar to the X-Men, it is possible in the future.

3 Cosmo the Spacedog Cosmo the Spacedog

Cosmo has made a few cameos in The Guardians of the Galaxy, but he's basically the best Guardian in the comics. Why not make him important in the MCU?

4 Nova Nova Nova (Richard Rider) is a fictional superhero appearing in American comic books published by Marvel Comics.

Nova is an awesome hero. Just google him and you'll understand. In fact, he has been possibly hinted to in the MCU.

5 Man-Thing

Man-Thing is a swamp creature that protects the Nexus of Reality. Need I say more?
He has been mentioned in the MCU before, so is it possible?

6 Beta Ray Bill

A galactic anthropomorphic horse that is one of the few in the galaxy that can wield Mjölnir. Much like Man-Thing, a statue was built in his honor on Sakaar, seen in Thor: Ragnarok. A popular fan theory is that the old Avengers sacrifice themselves in Avengers 4 to save half the universe. If this is the case, Beta Ray Bill could take Thor's place, though it isn't very likely.

7 Howard The Duck Howard The Duck Howard the Duck is a fictional character appearing in American comic books published by Marvel Comics.

Forget the bad movie from long ago, the new Howard the Duck that made several cameos Guardians of the Galaxy should have a bigger role. He's actually a friend of Man-Thing, and Howard could help introduce the Avengers to Man-Thing.

8 Deadpool Deadpool Deadpool is a fictional antihero created by Marvel who appears in their comics. Deadpool's first appearance was in New Mutants #98 by Rob Liefeld and Fabian Nicieza in February of 1991. His powers include self-healing and super strength. He is regarded as one of the funniest characters in comics due more.

Everyone's favorite anti-hero, Deadpool is very funny and fits into the MCU. Except one thing; Deadpool would not work well if he was restricted by the PG-13 rating.

9 Wolverine Wolverine Wolverine is a fictional character appearing in American comic books published by Marvel Comics, commonly associated with the X-Men. His powers and abilities include a healing factor and his signature adamantium claws and adamantium skeleton.

Wolverine is an X-Men, but is apart enough to have his own point on this list. The only problem is he wouldn't work as being such a dark character.

10 Galactus Galactus Galactus is a fictional character appearing in American comic books published by Marvel Comics. Formerly a mortal man, Galactus is a cosmic entity who originally consumed planets to sustain his life force, and serves a functional role in the upkeep of the primary Marvel continuity.

It's a bit of a stretch, but it would work as the very end of the MCU, when they finally run it into the ground after a few decades or something.