I second @Hamex's suggestions...good choices!
If you want to try something Korean, maybe a drama that's more episodic? Like a crime or mystery drama? The cliffhangers for those were less painful for me. Mrs. Cop, Bad Guys and Vampire Prosecutor might work. Liar Game would also work (beware of the female lead in the kversion...jversion was less painful).
I also suggest Let's Eat. It's got romance and some mystery, but I didn't have the marathon urge. Word of warning though...lock your fridge before watching. Serious food porn! It was a cute watch and concentrates on the experience of enjoying food with family and friends. There are some quirky characters in it, too.
Other than that...maybe you could watch some mini dramas...like I Order You, Twenty Years Old, The Secret Message, EXO Next Door, etc.