I ditto this! A Luthor with powers would be likely interested in going whole-hog evil (the same way as he did in "The Phoenix"). Flying around meting out "evil." And then the fact that Lois was standing there (and getting her own version of the powers) would make her doubly desirable as the "perfect mate" because now she's also physically his "equal".

CLARK: No. I'm just worried I'm a jinx.
JONATHAN: A jinx?
CLARK: Yeah. Let's face it, ever since she's known me, Lois's been kidnapped, frozen, pushed off buildings, almost stabbed, poisoned, buried alive and who knows what else, and it's all because of me.
-"Contact" (You're not her jinx, you're her blessing.)