There's an older period drama - My Bratty Princess Rooftop Prince and Lovers have action, but aren't necessarily action dramas (tho you might have already seen them) :P I also like action/romance, but ones that don't end tragically are not all that easy to find :D
I found 'Poonsang' to be quite an interesting action movie with a subtle sweet romance; it's also not long.
@bakaleya: movies are always welcome! thanks @azndrama: i've already watched Rooftop Prince and it was really funny too. The first one is a bit too long but i'll give it a try. Lovers seems to be perfect for my hunger for action/romance dramas. Actually, i don't dislike the ones that end tragically :P @Mssankacoffee: i couldn't find Poonsang on MDL, can you pass me the link? Thanks a lot all!
There's Always , a k-movie , that have action because of the guy and have a beautiful love story :3
http://mydramalist.com/korean-movie/1814/only-you