I agree with the OP points.
I think the training and experience impacts need to be changed.
Historically the Luftwaffe had serious problems with training in WW2 - (interesting link
http://www.caselab.okstate.edu/ocharle/projects/lf.html ) and while we can crank out an interceptor in 110 days in the game, realistically you should get an inexperienced unit that is marginally effective. From the link:
The highest scoring pilot in the world, Erich Hartmann, talks of the replacement pilots he received into his Luftwaffe squadron. ``I get young men coming to my squadron in Russia with less than sixty hours' total flying time, and only twenty hours of that in the Me-109. They have to fly combat with such slender training. This accounts for most of our Eastern Front fighter losses... They can barely get the Me-109 up and back safely as it is, without fighting''
Maybe extend air unit production time to something similar to CAGs and give us a rush mode where we can crank out inexperienced units in short time periods.
Air units should also gain experience faster and unit experience should be a larger factor in air combat.
Even with training laws maximized and great practicals - there should be a limit to how fast you can get quality pilots.