** Disclaimer: This is my first contribution to CBM, so please be kind, lol. I will also mention that I have not read the entirety of the Planet Hulk comics yet so if that shows, my bad.**
So, on and off the past year or two (including recently) there has been talk about a stand alone hulk movie coming along in the next couple of years. A popular rumor has been that Marvel would adapt the famous Planet Hulk storyline.
For the uninitiated, the basic plot is that The Illuminati decides Hulk is too dangerous to be allowed on Earth so they send him away on a spaceship which ends up crashing on Sakaar, where Hulk is forced into Gladiator combat and ends up helping foster a rebellion and becoming ruler of the planet. While the idea of Hulk fighting Gladiator style against powerful aliens could certainly be entertaining, there are a couple issues that both Kevin Feige and Mark Ruffalo as well as fans have said there are with the storyline;
1) Marvel is not established enough for the Illuminati to form, and it would make some of their top characters into the bad guy. This has been mentioned more by fans, but it has to be a concern for the studio as well.
2) Both Feige and Ruffalo have stated that a Hulk film needs to feature Bruce Banner plenty, and Planet Hulk- if it stays true to the comics- basically cuts Banner out of the story entirely.
Now I've seen people in discussions and editorials here before talk about the first one, but not as much about the second.
Regarding the first problem; I can't take credit for this and I'm not sure who could originally since I've read it many times, but I like the idea of Thanos using the Infinity Gauntlet to send the Hulk to Sakaar near the end of Avengers 3; it would build a lot of tension with the Avengers losing their arguably biggest gun at the peak of battle, would be a logical move by Thanos to quickly and assurably dispose of the biggest threat to him on Earth, and would be a sound way to get the Hulk to Sakaar without turning the MCU's most popular characters into villians.
That does leave the question of how to return him to Earth; we would want him back at some point. I'm not sure what I think would be the best way to go there but I can think of a couple ways.
1) Utilizing a GotG cameo, at the end or as a post-credits scene they give him a ride to Earth.
2) One of the Avengers gets ahold of the Infinity Gauntlet (or maybe just the Tesseract) and use it to bring him back. This would mean Planet Hulk is likely to take place during the tail end of Avengers 3 but might not work given the time that passes in the respective stories.
3) Utilizing the Bifrost (either modifying it, or building another version if Jane Foster and co. manage to master the technology and make their own) Hulk is returned to Earth that way.
Both 2 and 3 could offer another path into World War Hulk if Hulk were to be ripped away from Sakaar at the wrong time (say after Hulk's son is born) making him angry and wanting vengeance for being brought back, rather than for being sent away.
Regarding the 2nd issue (not enough Banner), they could simply state that the device stuck to Hulk's chest that gives them some measure of control over him is able to force him to change back and forth and- thinking it will help them maintain control over him- they change him back to Banner anytime he isn't fighting in the Arena.
This could allow for some interesting dynamics and subplots. As Hulk is surviving and becoming more defiant in the arena, guards and other people representing the King could take be taking it out on him physically with him not able to defend himself. This could lead to other Gladiators who've been saved by the Hulk in the arena starting to defend Banner out of it which is the start of a unified resistance among them. With the Hulk realizing he can't blindly smash the problem away (moving Hulk away from the mindless brute), Banner and the "Other Guy" start finding a way to mentally work together and strengthen the link between the two personalities. Over the course of the film, this allows Banner to access some strength to help himself even if he can't fully change, and Hulk being able to remember and use more of Banner's knowledge.
While locked up Banner could be secretly studying the devices with the help of the other Gladiators that are used to keep them under control, and eventually finds a weakness that the Hulk is strong enough to take advantage of. It kind of his Bruce Banner his own "stuck in a cave with a box of scraps" moment to really own and embrace his situation with The Hulk. Hulk, being able to use this knowledge now, is able to disable these devices while fighting his toughest foe yet in the arena (perhaps a captured Drax, to set up GotG owing Hulk a favor, if Beta Ray Bill or Silver Surfer are not yet set up in the MCU), freeing the gladiators and allowing for the rebellion to begin. The rest of the story could then play out with few tweaks that I can think of being required.
Love the idea? Hate it? Falling somewhere in between? Let me know what you think in the comments below. Thanks for reading!