"We have are meraculious B-25 but what do we want next?"
I bet they've already got a P-39 model done up, ready to surprise us. It'll become the second tank strafer Hitech introduces in a row, after the B-25H. You won't do much damage to the tanks, but you'll be the one who lands the kill, not Mr Sherman with his single well-placed solid slug.
Obviously the Brewster Buffalo after that, at which point the planeset is complete.