The New 52, Corrected: Superman
What Happened: In sharp contrast to the brilliant and well-received Action Comics story of a Superman who had weakened abilities and worked to be a champion of the people, Superman was a story about...Superman's shiny new costume. Also there was a weird sort of semi-cuckold deal where Superman went to his no-longer-wife's apartment only to learn some new guy was banging her:
Yeah, I'm gonna pretend this never happened in my personal fanboy canon. DC can do whatever the fuck it wants.
What I'd Change: ...The idea of a New 52? Ah, fuck it. I'm getting tired of doing these, I guess. Anyway, what I'd change is probably the idea of Clark being a typical reporter. Clark's worked at the Daily Planet since 1938, and it's getting old. Superhero comics have a habit of doing a certain something because it worked really well when it first happened, or when someone tries something new that's a hit...even if "when it first happened" or "when it was a hit" was a decade (or multiple decades) ago. If you can't tell me why Clark works at the Daily Planet then there's no reason for him to be there--Dan Slott had Peter Parker leave the Daily Planet and start working as a scientist for a bleeding-edge technology company and it was the BEST THING EVER for that character.
So, let's try this: Clark's still at the Daily Planet (wait), but he's no longer a newspaper reporter there. He works for the planet's new media division, doing investigative journalism that takes him all across the globe, shedding light on harsh regimes, illegal slavery rings, drug lords and the like. You can still have him run into a ton of supervillains doing this, but he also returns to being socially relevant again, particularly when he runs into situations where he can't just laser eye his way out of things. Oh, and because if I'm not mistaken Lois is now the head of the Daily Planet's web division, Lois is his boss. If you're not laughing at how awesome that is, superhero comics aren't from you.
Why: Because Superman needs to matter again. And having him fuck around with how his costume works isn't going to make that happen. Yes, there's a risk of having Superman just...Superman his way through all the social issues I mentioned, but let's look at the truth: If you could ACTUALLY beat these problems with brute force, wouldn't we have done it already?
What I'd Keep: Wonder Woman being Superman's girlfriend. The New 52 has yet to change much of anything. And don't get me wrong, I've got nothing against Lois/Clark, but...I've got nothing against Clark/Diana either. And I'd love to see what happens when the more militant Diana clashes with her boyfriend over certain social issues. Though I think I'd also let Lois know who Clark is so he can have a platonic friend share his troubles with.