Honestly, I feel the writers didn't really do much for Luwin that wasn't in the books (and I really liked him there). I think it just shows what a good enough actor can do for a role, really bringing the character to life.
Also, a few choices on this list I disagree with. Osha being so low was a real shocker. I really thought Tena nailed it and disagree with pretty much everything you said in that writeup. I didn't get the "wildness" from her at all, in fact I felt that the absence of wildness was kind of the point of her portrayal. Also, Gillen gets too much flak for things that aren't really his fault and generally reserved for the first two episodes anyway. I felt he was great for the last eight, on par with his season 1 performance, it was just the first two he had problems with.
And of course, I would probably rank Iain McGlen at number 1 for supporting actors. I watched the episode you mentioned in his writeup last night, and I have to say, I really did feel that conflict and turmoil. I guess that's just the thing about interpretations of art-they're very subjective.
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