There was a lot happening in Avengers: Endgame that it takes several viewings to take it all in. One of the things you might want to pay close attention to when you watch it in theaters again is the drastic change in Hulk's situation.
We're not talking about him and Banner becoming Professor Hulk, but how the world has completely changed its perspective of the green monster. A Redditor by the name MrStark3000 has pointed out how things changed for Hulk after the events of Thor: Ragnarok.
In that film, a funny argument between Thor and Hulk ensues when the former attempts to recruit the latter to help him protect Asgard from his sister Hela. He offers to take his green friend back to Earth if he does. However, Hulk isn't all too thrilled to go back because he thinks he is hated there.
Hulk seemed genuinely sad about how Earth saw him in Thor: Ragnarok. Fast forward to Avengers: Endgame, and he has fans requesting to take selfies with him. In fact, the kids didn't even think about taking a picture with Antman or even Captain America and Black Widow, which goes to show just how things turned around for him.
This scene, while no doubt one of the more hilarious moments in the film, definitely offers something more that could have easily gone unnoticed because of how funny it played out.
Meanwhile, a lot of fans would have loved to see more of how Banner and Hulk came to terms with their situation and how they ultimately agreed to co-exist. After all, Infinity War left the two with so much to talk about.
As fun as Professor Hulk was, some fans also wanted to see him let loose like old times. He still has the strength of Hulk as demonstrated by the first snap. However, we didn't see Hulk smash in Avengers: Endgame, at least not as much as he did in the past. This might be an effect of the merge though. With Banner at the wheel, he might not be able to tap into Hulk's combat skills. However, some fans think this would have been the perfect reason for him to confront Thanos for what became of Black Widow.
Also Read: Avengers: Endgame Deleted Scene Hints What Thor Really Felt About Valkyrie