The framing device for the story; Rick wants to show the world that Hulk isn't as bad as people make him out to be.
The little girl's reaction to being saved the Hulk.
Doorway to Destruction Part 2
When everyone else comes back to rescue Hulk from the Negative Zone.
Hulk inviting Skaar to join the team near the end of the episode.
The fact that Hulk wasn't mad that Iron Man made a Hulkbuster unit to fight him, he was mad because Iron Man made Hulkbusters designed to take down his friends and family.
And after they foil the Leader's plan, Iron Man tells Hulk that he'll be decommissioning the Hulkbusters. Hulk's response? He tells Tony to keep one in case he or any of the other Hulks ever lose control.
Red Hulk admitting that while he may not like Hulk, he still respects him nonetheless.
Hulk feeling responsible for Rick, feeling that he's the reason he became A-Bomb and is in danger with the rest of the team.
The Incredible Shrinking Hulks
Skaar turning on the Leader to save the other Hulks, then admitting that he considers them to be family.
Of Moles and Men
Despite the fact that the queen of the Larva Beasts was now attacking Hulk's hometown and no longer Subterranea, the Moleman and his minions decide to help Hulk rescue his hometown from her instead of being ungrateful bastards as what would normally be expected from villains. When the threat is finally dealt with, Hulk acknowledges their efforts and gives Moleman back his crown and title as a reward.
The Moleoids and the people of Vista Verde getting along fine even after the battles over.
Planet Leader Part 2
Leader forces Hulk and Skaar into a fight to the death. If they fail to comply, Jen gets zapped to death by her restraint disc. So Skaar gets it into his head to let Hulk beat him.
Skaar: Skaar let Hulk win to save She-Hulk.
Hulk: No, we can find a way.
Skaar: No other way. Skaar force Hulk to fight!
Planet Hulk Part 2
Ego was willing to give himself up to let the agents escape due to them trying to help him.
Ego: Perhaps for your own self protection, you should abandon Ego.
The Hulks come across an Eldritch Abomination that makes their greatest fears come to life to gain power; Hulk's temper becomes hair-trigger and he becomes overcome with rage, A-Bomb deals with Bozo the clown before becoming one himself, Skaar is turned into an immobile robot and Red Hulk is weakened until he becomes a despondent weakling. Jen is rendered so cold she freezes solid. The whole episode up to that point is equal parts scary and a little hopeless, almost a Darkest Hour, as the entity plans to go to Earth to terrorize everyone else. However, what snaps then out of its influence and being possessed by its power is seemingly losing Jen. The entire team pulls together out of concern for her and reign in their fears with Red Hulk, having butting heads with her almost as much as Hulk, using his heat powers to melt her free. It really was an emotionally compelling moment, given how the rest of the show is.
Jen giving Red a hug after he thaws her.
Jen: Red! You saved me! (gives him a hug)
Red: (smiles) Aw, it was nothing Jenny.
Mayor Stan convincing the rest of Vista Verde that the Hulk's are still the good guys.
Mayor Stan: It's okay, their heroes in every sense of the word.
Mayor Stan in general really, not surprising considering just who he's based off of.
Mayor Stan: You know, we never gave up on you.
Days of Future Smash: Smashguard
While Hulk is busy teaming up with Thor and Loki in the past to keep Leader from taking the throne from Odin. In the present, the other Smashers have to fight the alternate Thor and Loki, now under Leader's command. The amazing thing is, Thor and Loki actually get along, really well in fact.
Leader: Use your brain trickster. Use the hammer on him!
Loki: He is my brother. If not by blood, then by battle!
Days of Future Smash: The Tomorrow Smashers
Hulk telling Junior that he's the real hero as he choose to do the right thing, rather then do what his father wanted. And was a better "Leader" then his father ever could be. With Junior saying Hulk would make a better father then his dad ever could.
Planet Monster Part 2
By the end of the episode A-Bomb goes to check the poll he created on his computer to find out if people now like and trust the Hulk. When the stat says only 7 people now see Hulk as a hero (like it did in the opening of Part 1) A-Bomb goes ballistic. The other Hulks tell him not to worry about what other people think. Once A-Bomb puts the computer down the stat starts to rise rapidly.