5 Planet Hulk Easter Eggs We Want to See in Thor: Ragnarok
Thor: Ragnarok has gotten an official synopsis, and it has confirmed some big story elements for [...]
The World of Sakaar
In the "Planet Hulk" storyline, we get to spend a lot of time getting to know the planet of Sakaar, an outpost for vagabonds and criminals, where the evil Red King holds a gladiator tournament where combatants fight to the death.
While Thor: Ragnarok will have a lot of worlds to cover, we're hoping that Sakaar gets its just due in terms of world-building, and isn't just a random place that gets superficially skimmed over.

The Warbound
A big part of "Planet Hulk's" storyline involved Hulk forming a "warbound pact" with other alien beings also incarcerated in the Red King's gladiator rings. These other characters in Hulk's warbound group became great supporting characters that helped humanize the Hulk, and inspire his heroism.
In Thor: Ragnarok we already know we'll see the character of Miek in Thor: Ragnarok, but other characters (like Elloe Kaifi, Hiroim, and Korg) are iconic parts of Planet Hulk that we want included in Thor: Ragnarok.

Caiera
The Sakaarian warrior woman who serves The Red King starts off as Hulk's most formidable foe, but over the course of the story, impressed with Hulk's heroism, she becomes his lover and wife. Eventually, Caiera gives Hulk two children, Skaar and Hiro-Kala.
Caiera is one of the most badass female warriors introduced in the 21st century (after all, she's the woman who tamed The Hulk's heart...); it'd be a big missed opportunity not to have her be a part of Thor: Ragnarok's introduction of Sakaar.

The Sakaarson Prophecy
Marvel fans have been asking for a proper Planet Hulk movie, and if we're to one day get there, Thor: Ragnarok needs to the use its introdcution of Sakaar, the gladiator arena and other elements from the story to set a strong foundation for what may later come. One way to start Hulk on a new trajectory in the Marvel Cinematic Universe would be by introducing the character to Planet Hulk's Sakaarson prophecy, as part of Thor: Ragnarok.
Once Hulk learns that in another part of the universe, he's a propheseid savior instead of the monster he's seen as on Earth, it would make sense for him to return to Sakaar seeking his destiny after the events of Ragnarok, rather than going home to Earth.

Surprise Final Gladiator
This is something that has been a big part of both the Planet Hulk comic book storyline and the Planet Hulk animated feature: As Hulk gets to the last round of The Red King's gladiator tournament, he's blindsided by the arrival of a final, incredibly powerful, Marvel superhero, who has fallen under The Red King's control. In the comics, Silver Sulfer is the surprise combatant; in the cartoon movie, it's Thor's Beta Ray Bill.
Some may think that having Hulk and Thor rematch in a one-on-one battle (after their bout in Avengers) is cool enough; however, it would be a great surprise for Marvel fans if the pair had to unite and battle a character previously unseen in the MCU - one who was a match for them both.

Honorable Mention: Sons of Hulk
Even if Caiera doesn't get the biggest introduction in Thor Ragnarok, it's still possible that she gets enough of one (as in, one night) to set up something truly big for the future: the sons of Hulk.
Marvel Comics fans know about the heroic Skaar, and his villainous twin brother Hiro-Kala, but the Marvel Cinematic Universe has yet to introduce them. Thor: Ragnarok could (literally) plant that seed, to be reaped in future Marvel movies to come.
