As a film franchise adapted from more than 75 years of comic book source material, the Marvel Cinematic Universe didn’t really need to invent anything brand new, and yet, it did. Not only are the storylines themselves now vastly separated from the annals of Marvel Comics, but there are also even some wholly original MCU characters out there forging a brave, new path through the Multiverse. Those MCU characters that aren’t from the comics may be few and far between, but that doesn’t make them any less important.
Nor does it make them any less enjoyable to most audience members. Really, if one thinks about it, the character arcs of most superheroes and villains in the MCU are already so drastically different from their comic book counterparts that they almost count as originals on their own. The MCU-only crowd just happens to be extra original.