Male:
Lee Min Ki - He is so quirky, that he would be able to pull off any role. (And can we get a drama/movie/mv where he doesn't die)
Jo In Sung - I really want him to do more movies. Mainly because they're more serious than dramas, for the most part.
Park Shi Ho - He has great potential and I kind of want hi and Moon Chae Won and Song Joong Ki to do a drama together, because I ship both of those xD
Song Joong Ki - Great talent. I want him to continue taking part in movies :)
Kim Bum - Recently saw 'Psychometry' and damn. I need a drama/movie, where he's a bad boy or some type of thief. I don't want it, I literally need it.
Joo Won - Need I say more?
Kim Soo Hyun - Loved his small role in 'The Thieves' and his current project 'You Who Came From The Stars' is amazing as well.
Jung Il Woo - I love how funny he is, his expressions have me cracking up all the time, but he can still pull of the more mature chraracters.
Ji Sung - The first time I saw him was in the movie 'My P.S Partner' and I thought I would never be able to unsee that character, but he proved me wrong in 'Secret' with his considerably dark character.
As for idol actors: Yoochun and Seo In Guk.
Female:
Jun Ji Hyun - Queen. I love her characters and she seems like such an awesome person as well.Not you typical korean actress, in a good way.
Moon Chae Won - Thank you for not picking the standard easy roles, you've truly shown how capable you are as an actress.
Song Hye Kyo, Shin Min A are also amazing.