Here are some new concepts I would like to see for Marvel's next MCU Movies, after Avengers 4:
Guardians of the Galaxy Vol. 3 was already announced, the film will wrap up Gunn's trilogy of "this iteration" of the Guardians, as well as sequel for Spider-Man: Homecoming. Other sequels to established characters like Doctor Strange, Black Panther, Captain Marvel and Ant-Man are inevitable. But let's get some new franchise blood in there, right?
2) Black Widow - Marvel is sorely lacking female-led superhero movies, and this fan-favorite character is in desperate need of a solo spy adventure. I would expect this to come out very shortly after Avengers 4.
4) Eternals - Gods aren't going to go away just because Thor isn't very active. This powerful race would be fun to introduce to the movies since the Inhumans clearly aren't going to make the leap. Sersi would tie her people to any Avengers crossover handily enough.
6) Hercules - The other Asgardian. With his people grounded on Earth, Herc could handily be around to save the day and be naughty, keeping Asgard a part of the universe.
7) She-Hulk - A character that is known for breaking the fourth wall like Deadpool, She-Hulk would be a great candidate to have her own movie.
8) Captain Britain - The Avengers going more global, with a flawed Brian Braddock leading the way.
10) New Avengers - We would clearly see Spider-Woman, Captain Britain, Sersi, Hercules, Nova and perhaps She-Hulk join established characters like Dr. Strange, Black Panther, Captain Marvel and Spidey. Perhaps fighting against Scarlet Witch.
11) Champions - Welllll, I would actually like a generic team like this advertised, but let's actually make the team consist of villains playing hero. A woman with psychic abilities could claim to be Moondragon, but in fact be Moonstone, etc. Making way for Thunderbolts, the sequel where they go all-out bad, of course.
12) Daredevil - Let's be honest: The Netflix series are amazing, and Marvel knows that the shows will run their course eventually. And by then, they will be household names and prime for a full-blown MCU movie. Daredevil, Heroes for Hire, Punisher, Elektra - these are some big characters.
13) New characters taking the reigns - New characters replacing characters like Iron Man, Captain America and Thor are inevitable. Some sort of reality-warp via Scarlet Witch would make this easy.