Lol, although what I'm going to recommend aren't dramas but historical movies, but yes, they have painfully beautiful male leads with long hair (in my opinion) XD
Duelists (Kang Dong Won as the role Sad Eyes truly looks like a character walked out from manga XD)
Kundo: Age of the rampant (Most of the time, Kang Dong Won has been the painfully beautiful villain male lead with expert sword-fighting skills, but when his top-knot cut, in just few monents, he became painfully beautiful long-haired devil villain male lead with expert sword-fighting skills, lol)