Has anyone read the Superman: Earth One graphic novel yet? I don't know about anyone else but that just screamed movie adaptation to me.
As for Singer's film...it was OK...but that's it really. The only really exciting part was the space plane sequence but after that there was nothing that could really top it, so they shot themselves in the foot a bit in that regard. I didn't mind all the links to the Donner films, but I felt it was a little too slavish and should have pushed a little harder to get out of it's shadow and try for something new. The result was neither one thing or the other and was, unfortunately rather mediocre. A real shame because I can't fault the casting or the performances, all were very good and I didn't notice any "bad" dialogue. Effects, set design, cinematography, score, all top flight material.
I suppose the biggest let down was Lex's "master plan" which made even less sense than in the old movie. I mean, OK, he breaks into the fortress, steals Kryptonian technology and uses it to...grow a barren continent thinking he'll hold onto it with three hired thugs and a helicopter? Riiiight.
The first part of that works fine for me, but I think a more logical and faithful approach should probably have gone along the lines of Lex stealing the tech soon after Supes disappears and reverse engineer enough of the surface tech to file some very lucrative patents that makes him a billionaire industrialist. Much better than scamming some old lady for her inheritance. When Supes got back Luthor should have owned half of Metropolis having bought his way into respectability.
And while I'm dreaming; the obvious villain then would be something along the lines of the version of Braniac from the DCAU. That is a Kryptonian AI that was on one of the crystals. Perhaps Lex "interrogating" it for more advanced technology and it somehow escaped. Perhaps infecting someone using the crystals? Either way it'd end with an actual supervillian fight, not some real-estate scam.