If you want some Modern Era kind of Romance, these three Korean dramas below have the best main couple (for me).
Because This is My First Life ( This rom-com drama has 3 couples but the main couple's story is still the best.)
Go Back Couple (This is also a rom-com about two divorced couple that found themselves back in time. )
Tomorrow With You ( This has some angst and adult scenes but the plot and character development was really beautiful. )
Edit: Adding Thirty but Seventeen to this list :) (This drama perfectly showcased two couples overcoming their emotional traumas together. )
But Alchemy Of Souls and Mr. Queen top the most chaotic and hilarious romance for Historical dramas for me. ♡