E-7 has a couple of subtle shape differences here and there, most notably the pointed spinner.
That's probably the closest parallel you'll find to the current P-47 situation. They just took the P-47N flight model, removed extra gas, removed a little weight, and put rounded wingtip 3D models on it.
No tweaking of anything 3D, and very little tweaking of anything flight-model (heck, the wing tanks still show up on the damage screen!)
Finding something else like that where the variant is different enough to warrant adding to the game will be very hard.
That said, I'm all for the E-7 or E-7/z!!!!