I dont like the bump map on the hat, it becomes too obvious once you see the profile part of it. I would displace it rather than bumping it.
I think that your skin shader could do with some work also, there doesnt appear to be any transluncency or a defined highlight (It's too diffuse).
I do however like the eyes I think that they work well in the model.
Alan
Technical Director - Framestore
Currently working on: Your Highness
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