As I am a HUGE firefly fan - that's where I got my Whedon start - I have to go with him as Jayne. Jayne's a tough guy, yet peel back a few layers and he has a warm, gooey center. Hamilton was just evil, with a bit of class, so not very layered. I do like Adam Baldwin in general. He's one of those actors that can steal a scene, even if he's only there for a second.
Nicole