Cdramas that are/have:seriousrevengebattleslogicalheart breakingmatureNot goofy, cheesy, light hearted etc. 

K-dramas about idols/singers/dancing. + idols+ music+ dance+ actors

MysteryCrimeSerial RevengeIf I missed (plenty), comment below and I will add. 

School K and J Dramas

Medical Dramas

Korean Historical Dramas I enjoyed and some I didn't 

Dramas that gave me heart flutters