Personally still think that the best two characters in GOT for both interesting characters and well acted up until this point is.....
Robert Baratheon and Ned Stark.
I don't think anyone else since the start have come anywhere near them for it yet.
My favourite characters so far simply because they are interesting is Davos / Ramsey / Bran. actually interested where they are going in general, the rest not as good.
side note for Bron, always liked him.
watched the 1st few episodes of series one at the weekend, and sean beans acting/ned starks character are really good at foreshadowing...you can see the fear in his face and him gradually losing control
Ned and Robert were immense. Even though I knew what was gonna happen to Ned, it still pained me to see it.