This is even dumber than Mks I-III.
USA vs England/Russia? Thats just stupid, and really kind of negates the entire point of a rotating plane set (ie, realism).
And beyond that, the USA would still dominate in terms of bombers, would hold her own in fighters, and be dead last in vehicles. She would also wail the crap out of everyone else in naval power.
UK/Russia would be essentially ****ed for the first 3 weeks, would be ahead in bombers initially, and onpar with everyone else for fighters. Later fall behind in bombers, have 1 vehicle for the first 5 weeks, and would still get face-raped in vehicles in week 5 and 6, even with the Firefly.
Axis would be behind in bombers between weeks 2 and 5, would be on-par for fighters between weeks 1 and 5, and then dominate the fighter area for weeks 5 and 6 with the 262. For vehicles, they would be essentially unopposed after week 3, and unless enemy airpower intervenes, could litterally just waltz right on to the enemy bases.
Again, you want history, go fly special events.