MCU: 10 Reasons Hulk Deserves Another Solo Film
2. So Many Great Villains
A key part of any superhero film is the super villain who opposes the hero. In many cases the villain can actually steal the spotlight, like Thanos or The Joker. On the other hand a weak villain can lessen a film's impact as you need to engage with the hero and the villain for the conflict between the two to really land. Malekith from Thor: The Dark World was a pretty unimpressive villain and hurt the film because of it.
The Hulk has a range of fantastic villains that could be translated to the big screen. The Leader is arguably his greatest rival and we saw his origin begin at the climax of The Incredible Hulk when some of Banner's gamma-radiated blood fell into Dr. Stern's head wound. For a more physical rival there is the Red Hulk, who is actually a transformed Thunderbolt Ross. Or you can combine both with The Maestro, a future alternate history Hulk who has been driven mad by a near nuclear apocalypse.
Simply put there are loads of cool and exciting villains that creators could use in a new Hulk film to really test Bruce.