HT - I think the idea will work but it's going to also put subtle pressure on game play. Players on the high-numbers side will tend to shy away from getting into big furballs and fly more conservatively to avoid having to wait. At least on the short term "ganging" will likely be more prevalent and in that circumstance the feeling on the low-numbers sides about being ganged will just be more pointed.
I like the idea of increasing the vulnerability of field resources on the high-numbers side, which I think has been said before in this thread, but I don't think it will work alone. What might also work, is if it's coupled with late war, normally not perked rides, needing small amounts of perks for the high-numbers side (la7, p51d, 109G10, ki-84, etc.). Link the perk changes directly to the numbers so that as a side's numbers increase, the late war rides start to cost something and if the numbers disparity continues to increase, have the costs of late war rides go up.
This will "fair up" the fight and give the low numbers sides the reward of extra perks. 2 birds with 1 stone.
Cheers,