Dr romantic, both seasons for kdrama. Iss pyaar ko kya naam doon and bepannah for indian dramas 

The Romance of Tiger and Rose

Easy-peasy - The Untamed - I'm surprised how no one has recommended it till now

Live Up to Your Name 

But it was in deed difficult to decide.

Like you, I like Empress Ki too. And I agree that Nirvana in Fire is great, but yet it doesn't have almost any romance.

You are my glory ( amazing chemistry , less conflicts and stupidity)

It's Okay to Not Be Okay of course. The one K-Drama everyone should watch even if its their first and only K-Drama in their life. To this day my favorite of them all :D  

hmm...well I liked 'My beautiful bride' very much...

My Mister   Just about everyone involved with it says it is the best project they've ever done, and are so proud of it.   Every episode builds off the preceding one in a kind of seamless beauty. 

The only bad thing is that it has spoiled me for K-dramas, as I keep hoping for a  My Mister level of brilliance, but nothing else has ever come close.   

https://mydramalist.com/25172-my-ajusshi

My favorite of all time is A Love So Beautiful. If you're interested in Chinese youth dramas with classic tropes, give it a shot. :)