I took a look at the data from the first playtest with
@Prof. Garfield . Attached is an excel file showing the relative strengths of our air (and my flak) forces from turn to turn (I checked every 3 turns). You'll note you won the game in 58 turns. A few highlights:
I was able to basically keep up with losses until you invested in Spitfires heavily around turn 21 - from that point forward it was possible for you to knock out more fighters than I committed and I had to be careful where I deployed them.
Attacks on D-Day significantly weakened my defenses - I went from 24 day fighters to 15 from turn 45 (I believe one turn after D-Day) to turn 48.
Some dramatic jumps were possible in Allied aircraft production - especially bombers "late" game. For example, on turn 54, the Allies had 11 strategic daylight bombers. Three turns later, they had 44. Likewise, on turn 51, you had 5x A-20s. By turn 54, you had 34.
I was able to significantly increase my flak defenses throughout the game, though I question how great of a decision that was. I started with 19x 88mm Flak batteries and 2 flak trains. I reached a high of 55 and 38 by turn 42. I suspect they will be more useful in the next version.
By game's end, the Allies could field 153 aircraft to the German's 18 (of which 1/3 were jets).
The most jets I was ever able to field was 9 (turn 56) but this would cost a staggering 4,500 fuel points to use all of their attacks each turn. I was never able to achieve anything close to this in fuel production. Granted, jets are best used to attack 3-5 times and then land somewhere far away, but even 2,250 would be completely impossible.
I don't really think the Allies have much of a production problem in this scenario. I get your point that with the changes they won't have as rapid a buildup, but it shouldn't feel like 1945 by turn 58, anyway. It probably needed a tone-down.