Looks good, I know it's still early in development, just a minor detail, Federal soldiers were issued a white shirt to carry underneath, I would like to see it sticking out of the cuffs.
And greatcoats were only carried by some troops, usually they were handed to the quartermaster and then re-issued in the fall to be used in the winter. It was probably more common, at least in summer to have a rolled up blanket that was on top of the knapsack. The color was usually grey but some regiments used white, hope this can be customized by the player.