First off, the composition is good, and I think the placement of the person in the frame is good, but i wish his hat wasn't cut off by the top edge of the frame. The coloring/and shading is very nicely done. I like how you used other colors in the black area other then just black. Also, it's great that you attempted to be historically accurate a far as the badges and such. On that note one thing I did notice with the badges (is that what they're called?) is that the perspective is a little distorted. I get the impression you were trying to show how that area curves away, but the way the badges decrease in size a little drastically doesn't quite look right. Other than this, the perspective and proportions seem to be spot on.

All in all I like this piece a lot. It's pretty bold and somewhat original, and I think the character is really pretty stunning.