I can recommend you some dramas from Taiwan and China as well:
From Taiwan I particularly liked:
Mars, actually it's the best Twdrama I watched not my number 1 but still the best, and we can't help but fall in love with the main couple.
In a Good Way set in the 90's and I think it's the best drama I watched set in that era, The main couple is so sweet and adorable, the friendship was amazing andth e music just pure masterpiece too.
My Lucky Star, it's my personal favorite, I know it's not the best Twdrama out there but I loved it from the beginning to the end, I love the development of the main characters in that one and Jimmy Lin is such a gorgeous Man. The only problem is that the main girl is dubbed since she's Korean. The Ost is perfect too and generally I think the drama is very addictive.
Bump off Lover, okay this is not a romantic drama, don't expect cute scenes or anything it's more of a psychologica dramal but I was so impressed especially that it was a first for me watching such an intriguing drama with a mystery feel from Taiwan. Highly recommended.
As mentioned above, Black and White , In Time With You and, Autumn's Concerto and It Started With a Kiss were good dramas too (I have a preference for second season of It Started with a Kiss "They Kiss Again").
From China:
Back in Time, I'm currently watching it and despite I kinda disliked the movie in the drama the friendship part is more developed and we can feel the strong bond between the 5 friends, it's not dubbed. A very refreshing drama in my opinion.
Battle of Changsha, it's a drama set in the 2nd SIno Japanese war but our main couple has some cute and sweet scenes, definitely among the best dramas I'ever watched and Highly recomended as well.
I watched many others Chinese dramas but those are historical, if you want some recs don't hesitate to ask.