Darn. I hit submit too quicky.
Okay, voted for Roger because well, I adore Roger, dysfunctional alcoholic though he may be. He is the reason I bothered to keep watching DS. Edmond's early work in the series is marvelous and frankly, before they diminished the character to a walk-on possibly one of the best things about the show.
If I had been more careful with my voting, second choice would be Joshua because I thought Edmonds totally nailed that part. He brought such nuance and dimension to the role. He starts out as being this relatively nasty rigid cold man, convinced that he knows the world and his place in it, and by the end everything's been totally upset. Brilliant portrayal.