I like the idea of the Kents being alive. If for no other reason than dead parents being a superhero cliche. Besides, he already has one set of dead parents.
I know the Kents being dead was a staple of the Pre-Crisis Superman. But I never quite got Pre-Crisis Superman. There are a number of DC characters where I like their Pre-Crisis versions better than their modern versions (Flash, Hawkman, Metal Men, Elongated Man, the Justice Legaue from back when they hung out with Snapper Carr and before they got all self-important) but Superman isn't one of them.