I doubt the actor is anywhere near as evil as the character he played. If he were, he probably would have had a "tragic" accident on set. That he smokes a pipe says he may well be a decent fellow. The sight of King Joffrey smoking a pipe, though, does no favors for our hobby. If only they could have captured photos of him eating kale chips or hugging a politician...
It takes as much, or more, acting ability to play a villain as a hero. Some of the greats have done magnificent villains -- Edgar G. Robinson, Jack Nicholson, James Earl Jones, Gloria Swanson, Bette Davis, and so on.
I heard he was planning on giving up acting for now to concentrate on his studies. I believe the last statement he made was just that and that he doesn't know if or when he'll ever act again.
Didn't know he was a pipe smoker, that's pretty cool.
Of course, if he studied philosophy, he career path would likely (though not categorically) to teach, in which case his acting skills would be fully utilized.