Extraordinary Attorney Woo, My Mister, Signal, Stranger, Under the Queen's Umbrella, Hyena, Good Manager, Crash Landing on You, Are you Human Too ? , to name a few. My personal bias isn't towards straight rom-coms. No matter how gorgeous and charming the FL lead is, there usually has to be enough action, intrigue and/or evil scheming people to keep me interested. Your mileage may vary, of course.
Happy viewing. Even if you never move on to Chinese and Japanese dramas, Korea has produced so many good ones.