i dont know any supernatural k-dramas other than what you've listed, but there are LOT of j-dramas that fit the bill. too many to mention really. i dug Vampire host, but it's REALLY campy.
as far as romantic comedy k-dramas like the ones you've listed, try these with some of the same actors
Mary stayed out all night (it's got Jang Guen Suk as the male lead)
Lie to me (kang Ji Hwan, i dont know the female leads name but she's totally awesome)
Personal Taste (Lee Min Ho)
just genreal suggestions:
Bad guy- melodrama
Protect the boss-romantic comdey