I don't really think that the mustache needs shading really, since he's going for a cell-shaded style. Maybe do some AA on the top of the hat, but other than that
This might just be me but...
I think the feet and arms need to be longer.
The mustache has no shading.
The top of the hat needs to be higher up.
And you might want to get rid of the banding on the hat.
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