Characters - America Vs Russia

My favourite idea is probably 'America Vs Russia'. I have done a few character designs, which are shown here. They are very stereotypical as I wanted it very clear that ones Russian and the other is American.
I made the American a cowboy because Houston, Texas is where NASA is and Texas is known for its cowboys so it made sense, when you thought about it.
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I'm not very keen on the bottom left Russian. It just doesn't look right.
So far I like the the top right American and the top left Russian. I think that I will have to change them slightly as I would like them to have the same sort of animation style. This could possibly be done by giving the American more of a curvy shape and eyebrows like the Russian.