Goblin is visually stunning, well written, and far away from being an average kdrama. The sets are wonderful, special effects are great, and the OST is a delight to listen to. In that terms, Goblin is the best drama I've ever seen, but it's not even close to being my favorite romance (but the bromance is just epic). I guess I wasn't completely sold on that part (I couldn't get over the age gap, and FL being a highschool girl), but I can still appreciate a good thing when I see it and I would definitely recommend that drama for everyone to see.
Most enjoyable drama to this day for me was Jealousy Incarnate - quirky characters, hilarious situations, fantastic chemistry between the leads, romance, love triangle, bromance, you name it. This one and The Master's Sun are easily the best rom-coms I've seen so far.
Fav action drama - God's Gift: 14 Days (Defendant & Tunnel are also great!). The story kept me on the edge of my seat, and it has my favorite leads ever - a smartass bad boy ML and a strong FL. No romance though, but you can feel the sparks flying anyway.
IDK about you, but I'm always in a mood for a story about teaching bad guys a lesson, so that's where the 38 Task Force comes in (Chief Kim too!). Great cast, whip smart dialogue, comedy and clever schemes. Who knew that catching tax evaders could be so much fun!