The girl on the right's head is a bit small, but you already mentioned that someone else did the lineart for her. Overall, though, it's very excellent and delicious. I wonder what the Yellow text is saying?
It's funny, because I translate military stuff into terms of either Red V. Blue or Advance Wars.
In AW, Red is "america" or Orange Star, Blue is "russia" or Blue Moon, and Yellow is "japan" or Yellow Comet; so the Yellow army's foreign language and poor grasp of the Red language definately relates.