For Kon, I'd focus on him moving to Hawaii on a whim and eventually sticking around to become its premier superhero.
Superman has a LOT of minor villains who are only "minor" villains because they tried fighting Superman.
I mean Teen Titans(Beast Boy, Cyborg, Raven, Robin, and Starfire) vs Scorch, Livewire, Puzzler(yes the woman Superman beat by stuffing her into a trashcan), Blackrock, and Parasite? Have fun guys! Any one of them, yes, even Puzzler, is someone who could give the entire team problems. Yes, Superman can stuff Puzzler into a trashcan. But Robin? Good luck dude! You're gonna need it! Oh and Robin fighting Blackrock? Yeah.... if it's the alien Symbiote version? Fighting Zod would be easier. Zod at least has a weakness to Kryptonite.
I was always a bit disappointed that Puzzler never used her brain for anything. The original Puzzler was themed around puzzles and games and the name seems tailor-made for a gimmick villain who tries to outwit and outplay Superman. But nah, it was just the jigsaw piece power again and again. She could have been a sort of crossover villain. A gimmick villain who has a superpower to use as a trump card or to get out of tight scrapes. But alas, no. (Unless it's changed since the last time I read Superman comics)
I always wanted to see a Twin Peaks-style show about a young Jonathan and Martha Kent raising a baby Superman while discovering the secrets of the DC universe through a small town lens.