The common complaint/excuse that Superman's "over-powered-ness" limits the amount of suspensful stories that can be told with him has always struck me as less an indictment of writers' abilities than the character's. Technically speaking, Superman and Batman are BOTH "all powerful" when the story calls for it, just with a differing explanation ("I'm Superman" versus "I just happen to have a gadget for just such an occasion," typically) and "vulnerable" by the same token.
"Superman II" solved the problem nicely: Bring in an enemy that matches him. There's HUNDREDS of enemy characters running around the DC Universe - ALL of which Warner Bros. already own, by that token - who're supposed to be as-strong or stronger than him, and that's not necessarily including "magical" characters for whom strength is largely irrelevant. Or they could always, y'know, just MAKE ONE UP
Otherwise... for pity's sake, the character is an ALIEN with the power of a god who has to pretend to be an average schlub to avoid blowing his cover so he can use an alternate-identity to fight crime. Can it REALLY be that hard to get 90 minutes of story out of that?