This would be an entirely new take on the character, and understably not liked by all, but if I were writing Superman, I'd change whole universe up a little bit so that Superman has his powers only because he's the sole survivor of Krypton. The Kryptonian race would all share a kind of energy wavelength, almost a spiritual connection, so that when Krypton is destroyed, Kal-El inherets their sort of metaphysical energy, and it's activated by the yellow sun.
I just never liked the idea that Superman is so powerful only because he's from Krypton, or the idea of one race of people so much more powerful than all the rest, even if there's only one left. Basically, Kal-El and any other Kryptonian would be ordinary humanoid beings without superpowers if Krypton and its people hadn't been destroyed, even with the yellow sun. Again, I know a lot of people wouldn't go for that, but that's just me.
Also, one plothole that should definitely be fixed is exactly why Superman is the only surviving Kryptonian (or even if he's one of a handful) I mean, Krypton was supposed to have been one of the most advanced civilizations in the universe. I imagine if they were so advanced they would've explored the universe, and founded colonies on other planets. Realistically speaking, there should be Kryptonians scattered throughout the universe. But I don't like that either. They should just explain why seemingly no Kryptonians ever left Krypton at any point during their history.