The end of the love triangle killed the books, but I honestly think that making Superman a single dad is a cure worse than the current disease. Sort of like trying to revive a corpse by setting it on fire.
Superman is not Spider-man. He's not even Batman. He's a "wish fulfillment" character on some levels. When you start saddling him with a wife and/or a kid and/or make him a single dad, you're making him a different and, in my opinion, not terribly successful, character.
