Silver Surfer

Stepping outside of Earth's atmosphere, we find quite a few superheroes Marvel could STILL use. Some of them (like Nova and Adam Warlock) will certainly be introduced in upcoming movies. The Guardians of the Galaxy franchise is perfect for such characters.

Unfortunately, none of these heroes is Silver Surfer. Originally a literal herald of death, the Silver Surfer becomes a hero after meeting with the Fantastic Four. He’s exiled to the planet he saved after his humanity is rediscovered and he goes against his master.

After the Infinity Stones are all discovered and placed with various superheroes for safe-keeping, seeking out new sources of power could be the catalyst that pushes the shared universe forward. And what could be more appealing than the Power Cosmic (which is vague, but extremely powerful, nonetheless)?

The Silver Surfer, with his tragic backstory, would fit perfectly. Except that he won't, since Fox owns him.