@kar you should really start on Love in the Moonlight. It's incredibly good and Park Bo Gum is just amazing!!
@IzzyDramaLover for you I'd really recommend two from your list because they're in my top 5 favourite: Splash Splash Love and Signal. You won't regret watching these two. SSL is really cute and romantic - only 2 episodes in, and Signal kept me hooked until the end :)