Wow, Dwight! This is excellent!
Rarely do we get to see casualties. Lends a very powerful punch to the diorama. I think we sometimes forget what these machines we love were designed to do.
I concur with the observations made by the other distiguished gentlemen, and will add one of my own: did you drill out the machine guns on the Pershing? Maybe you did, but on my computer they do not appear to be drilled.
Other than that, some dust on the floors, a bit of metal showing on the tracks, and I'd say you've got quite the masterpiece there, my friend!