As i should have said Kal-El without his super-intelligence is still a genius of the caliber of an Edison, Einstein, or William James Sidis. A genius with Kal's super-knowledge would be (to us) virtually indistinguishable from a super-genius.
Even only a moderately bright guy, with super data intake, super speed thinking, and super recall on pre-Crisis Superman level, would still come across as a total genius. He's probably living a lifetime between ticks of a second, and has a database floating in his head that'd make the folks at Google and Encyclopedia Galactica drool with envy. That's not to suggest that Superman is "just" a moderately bright guy, but those powers sure could go a long way.
As far as innovativeness, I tend to think that Kal-El is roughly Jor-El's equal, though both are below classic Luthor and Brainiac on the totem pole. I don't like Kryptonian science being so horribly super. Otherwise, why didn't they save Krypton, or prevent Brainiac from taking Kandor? Kryptonians as a whole are horribly status quo-focused, so it's hard to fathom their being great innovators. (The house of El must have an "innovative" gene to them.)
I've always figured that Luthor was mutated in the accident that caused him to lose his hair, raising his genius level even further, because that's the only way he'd be able to compete with Superman's prodigious intellect and mental abilities (let alone those physical powers of his). But, he has a mental block thinking about the nature of his own super-intelligence, else he'd realize that he has Superboy's accident to thank for it and it'd sicken him to the core. So, we never hear of it.