I think people keep focusing on the witty banter side of his character, and keep forgetting his supposed to be able to stand there and just look at you and have you get an impression of a savage bastard just barely restrained.
See, that's just my point. "Savage" and "just barely restrained" don't suggest "subtle" to me. But I take your point about the actor needing to tone it down.
And I think both Browder and Fillion have shown themselves capable of playing characters with dark, dangerous sides underneath flippant exteriors.
Maybe Christian Bale or (gasp
) Hugh Jackman? Other than the penchant for showtunes, the Jackman seems pretty wild...
Well, let's face it, Calhoun basically is Wolverine. However, I've always felt that Jackman's Wolverine falls short in precisely that area: I've never gotten the sense that he had that kind of savage fury smoldering in him.