-I strongly prefer sageuks over modern dramas, but it seems like most people are the reverse. I usually only watch modern dramas with a plot that's very unusual and wouldn't happen in real life (i.e. ghosts, FL pretending to be a boy, time travel, some form of fantasy, etc.)
-I won't watch dramas without a lot of romance. Of course there needs to be some plot framework, but I'm not one of those people who's all "I'm tired of romance, I need something more interesting." I'm a total romantic and want plenty of it!
-I don't care about k-pop, and get annoyed when a drama has an idol in a smaller role and people scream over him and get mad when he's not on screen and ignore the plot and rest of the cast. I'm looking at you, Viki commenters. Go watch some music videos if you want to see him so badly.