1. A problem that can't be punched
Superman can do pretty much anything he has to do, physically. If the bad guy can be punched into submission or thrown into the sun, then there's no real conflict or threat in the film. In Superman Vs The Elite, there is a moment where it really looks like Manchester Black and company may have beaten the Man of Steel into submission. It only lasts a moment, but the apprehension really engages and makes the climax all the more satisfying. Superman needs to do more than fly up and punch something to engage the audience, the ending of Superman The Movie actually does this well, but the whole time-travel thing lets it down a bit.
2. John Motherfucking Williams!
I like the work of Hanz Zimmer. I own a few of his albums and think he was a great fit for the Nolan Batman franchise. But seriously, why the hell was he brought onto Man of Steel? Williams' Superman Theme is one of the finest pieces of soundtrack work ever and even the Lego video games recognise this and work with it. I'm not ashamed to admit that when the brass starts up, a chill goes up my spine, even in the bad films. A great theme, forever tied into the character, why the hell would anyone not use it?
3. A man can fly
Somewhere along the way, Superman lost the sense of wonder that used to hang around him. Superman Returns tried to bring this back, but fell short somewhere. In this age of cheap and nasty CGI effects, seeing a man hanging in the air just isn't that impressive; but it really needs to be. Superman needs to evoke a sense of childlike wonder in adults, and to do that, he needs to be the adult take on Peter Pan, just hanging in the air in the way every child has ever wanted to do.
4. The Man of Tomorrow
Everyone in the world knows that Superman is the "Man of Steel". Seriously, most people in developed nations can name at least three of his super powers, so why keep harping on them? What good Superman comics do is show that Supes is the man that we aspire to be, the man that we all could be if we were a bit less selfish and put the greater good before our own. The original film did this so very well, but a new balance needs to be struck in the postmodern cynicism of the 21st century.
5. Hire a decent actor
Christopher Reeve was the perfect cast for Superman and every new take will be unfairly compared against him. That said, try harder than Henry Cavill dammit. He needs to be Clark Cent in one moment and Superman in the next, so cast wide and make sure he's locked down before you cast anyone else.
6. Superman is not Jesus
Seriously, stop trying to make Superman flying Jesus. For starters, he's an analogue of the European Jewish migration story, so the theological influence is clearly Moses, not Jesus. Superman is not here to save us from ourselves or die for our sins, he's here to show us what we can be. He is the prophet, not the messiah. That's right, Superman has more in common with Mohamed if we're sticking to the Abrahamic monotheistic faiths as exemplar. It may honestly be better to discard the entire symbolism here and focus on the "Man of Tomorrow" factor as mentioned above.
Well, that's my take, for what it's worth, what's yours? Long for the return of the Donner/Reeve combo or prefer the bloodthirsty Snyder smash?