While I appreciate the universe being interconnected, with Brainiac being tied to the origins of Kal and Kara, I do like seeing the possible dark future of our own Earth reflected in Krypton

I like how SyFy's Krypton did both with Brainiac being the main threat to cause Krypton's core to be exposed, but also it was indeed years of neglect by the council that leads to it still.

I prefer Krypton being destroyed by both natural causes and a willful ignorance of science because that story highlights the tragedy of Kryptonians as a species. They could have escaped their own destruction. They simply chose not to and that's why Superman works really hard to protect the Earth. He wants to show humans that they don't have to make the same mistakes Kryptonians did.

A villain getting revealed as the destroyer of Krypton doesn't work because it would inextricably tie him to Superman's origin, the same way Joe Chill is tied to Batman's origin. Let's say that Brainiac turns out to be responsible for Krypton's destruction, What's Superman gonna do? Attempt to take revenge? That's not who Superman is.

Krypton's destruction did not affect Superman the same way the deaths of Thomas and Martha Wayne affected Batman. Oh sure, it's always there, on the back of his mind, but never to the point of self-indulging tragedy.

Brian Michael Bendis tried to present Rogol Zaar as the destroyer of Krypton and that clearly didn't work.

Yeah, it being presented in a vengeance type story doesn't work for Clark as Rogol Zaar showed. Though one thing Brainiac in particular does is of course for Kara Zor-El.

Of course, the problem with Rogol is his identity as the destroyer of Krypton didn't change that much for Superman in the long run. When Superman heard about what he did, he was like "Okay. Cool, bro." and he just went on, business as usual.

Supergirl herself was more concerned about Empress Gandelo than Rogol Zaar and he is the guy that supposedly destroyed Krypton.

Also, am I really supposed to take Rogol seriously as a villain? He is constantly propped up by the story, other characters and even himself as a fearsome warrior, a veteran of countless wars, but his usual strategy is basically attacking hard and fast. Superman is just taking on an incompetent brute with an overhyped reputation.

Yeah, the factor of not being that impressive a foe also brings him down compared to Brainiac who was an interesting foe even before he had hype.