I 've seen korean drama from 2003 to 2017 and I've came to this thought:
2003-2011 (or 2009) kdrama have lots lots of misunderstandins with second male leads and stupid quarrels between the couples whereas the 2012-2017 kdrama are more down to earth and logical about the plot and persons' characters.
Take for example Full House, Goong and Boys Over Flowers. Though I liked these drama, as time passed I realized how stupid they were in some points.
Think about Healer, Pinnochio and Mask! No match!!
What do you think?