Marvel Comics has dozens of comic characters stretching from before the beginning of existence to the very end of everything. It's featured Barbarians, soldiers of fortune, supervillains, electric monsters, Spider-people - everything you could imagine, and more. Most of the things you've seen in the MCU come from comics that either are or were cancelled.
Unfortunately, that doesn't seem to be changing anytime soon as the MCU keeps taking more and more things from genius comics that aren't published anymore. Pretty soon series like the Future Foundation, The Ultimates, and Young Avengers will be as well known as Loki, Nick Fury, and Spider-Man, due in part because Disney's premier superhero franchise keeps taking cues from them.
Marvel publish dozens of different books every year, but these ones are long overdue a comeback...
11. Young Avengers
Avengers: Endgame was one of the best superhero movies ever, and it was full of stuff - endings, mostly, but a couple beginnings.
We saw Spider-Man step up and help save the universe, we saw Ant-Man's daughter grow into a teenager, which is how old she is when she becomes the superheroine Stature. We're supposedly getting a new, younger Black Widow and Endgame introduces us to a younger, girl Hawkeye. There's a zero percent chance a Young Avengers film isn't on the horizon.
Which makes it the perfect time to bring back this series. Young Avengers was the breakout hit for Wicked+Divine creators, Kieron Gillen and Jaimie McKelvie - the latter of whom designed the Carol Danver's Captain Marvel costume. It featured a bunch of young Avengers, including - at times - Kid (and later, Young Adult) Loki, Miss America, Kate Bishop AKA Hawkeye, and the children of Wanda and the Vision. It's a fantastic series that's up there with Brian Bendis' Spider-Man run.
But since its last, mind-blowing iteration, the series has been languishing. However, now is the best time for it to come back, just in time to catch the extra eyes the MCU's version of the Young Avengers is sure to bring.