The Marvel Cinematic Universe is a big place, with a mysterious future totally unknown to fans. The entire shared universe as we know it will come to a head with Avengers 4, resolving the horrifying cliffhanger that ended Infinity War. Aside from Spider-Man: Far From Home, the MCU's plans after Phase Three are a mystery. And while this may be the source of anxiety for the fandom, it also opens up the future to vast possibilities. Just about anyone could get their own movie, maybe even Mark Ruffalo's Bruce Banner/Hulk. After teaming up with the God of Thunder in Thor: Ragnarok, he's got another Avenger he'd like to appear with: Scarlett Johansson's Black Widow. As he tells it,
Well, of course, there's always the Banner-Black Widow combo, which I think is always a good combination.
The man has a point. While only a tertiary plot line in the first two Avengers movies, the MCU set up an early romance for Natasha Romanoff and Bruce Banner during Phases One and Two. But when The Hulk took a Quinjet and departed the planet at the end of Age of Ultron, that plot line was all but abandoned.
It's been interesting to see if/how Black Widow and Bruce Banner's romantic plot line is addressed in Avengers 4. It was seemingly mocked during the events of Thor: Ragnarok, and it seems like she and Cap may have their own connection from their years in hiding. But if the still developing Black Widow movie is looking to give her a partner in crime, Bruce Banner would definitely be an interesting choice.
In his same appearance on the podcast The Marvelist, Mark Ruffalo also addressed the Disney/Fox merger, which could potentially bring characters from the X-Men franchise into the Marvel Cinematic Universe proper. In that case, Ruffalo (like everyone else) would love nothing more than a movie with Hugh Jackman's Wolverine-- granted the actor comes out of retirement from the character.
It'd be cool to see --- I mean, people talk a lot about Wolverine and Hulk hooking up, I think that would be a really great combo.
Once again, a solid point. Wolverine and The Hulk have both teamed up and clashed throughout the years in Marvel comics, and fans are eager to see them finally meet in live-action. But studios' legal rights to the characters have prevented them from meeting, with 20th Century Fox maintaining control over the X-Men for the past decade and change. And with the Deadpool franchise also breaking records, the time has never been more exciting to potentially merge the franchises into one giant cinematic universe.