I would like to point that IT is supposed to be scary. Lightheartedness clashes with what horror movies are trying to achieve: to scare the audience. I don't think we are in disagreement.
I agree that quality brings fun. Lightness does not automatically imply a good story.
On my part i want a lighter Superman. Serious take is everywhere. Whether the DCEU which i like or the atrocious Injustice which i hate and stay far away, darker takes are in rage. I want something else in my books. If i want to be depressed i can go see the news. Why shall i open a comic book?
I think the concept of Superman is by itself such that it suits a lighter take. He is an invincible alien who flies and shoots laser from his eyes. He is supremely strong but is stopped by a green rock. He puts on glasses and people don't recognize him. These are to some extent goofy and childish. These are some fundamental aspects of Superman. You can't take them away. One has to add things to make the stories serious.
Similarly Batman suits a darker take. He scares criminals. His enemies are psychologically twisted as he himself uses psychology of fear to achieve his ends. This is the fundamental idea. You can't take it away from Batman. If you take it away you have something like Batman and Robin of Joel Schumacher.
If you take Superman too seriously the stories will become boring in my opinion. There is a tragedy but that does not affect him so much. Batman saw his parents shot before him when he could understand what was taken from him. He lost his family and security. Spider-man lost his uncle when he was in high school. He lost his family (Uncle Ben) and may loose again (Aunt May). But Superman was a baby when Krypton was destroyed. There is no reason that it would dwell so heavily on his mind. In many takes they try to make him sad. But using common sense why should he be sad? He is super strong. Nobody can hurt him. He can fly. He can shoot lasers from his eyes. Let me repeat he does not require a laser blaster like Han Solo. His eyes shoot lasers! He is so cool! Why would such a person be unhappy? Someone like X-Men would be unhappy because they are stigmatized and hunted. Superman even though an alien is handsomely built and looks like any other American. The Kents raised him lovingly. Making a few adjustments he can live quite easily with the people. Why shall he be unhappy or sullen?
He shall be doing awesome things like punching rogue angels, or fighting robot dinosaurs. This suits him a lot more than walking all over America for...reasons.
I love Goku but sadly for all its awesomeness DBZ has not aged so well. I can enjoy Superman TAS which came at that time even now. But DBZ due to its padded stories and repetitive plots is almost unwatchable now. And what is wrong with Lois and Clark? Its target audience was different.