I'm a male kdrama fan too and yep I watched a lot of Kim So-eun's dramas and movies purely for her, of course I liked them, but a lot of them I wouldn't have watched if it was not for her. So yeah as a straight guy I also watch more for the actresses, but its of course not a necessity, if the drama is good overall is more important. :)
There are certain dramas/movies that I started to watch because of a certain male actor too, but then its for their acting skills, and not their looks. :)
Also I never watch Western romantic stuff, I don't like it, but I do seem to really like Korean romantic drama's and movies for some reason. So often I switch between crime and more romantic dramas. :)