AH is an air combat sim with a strategic element to it; thus it simulates war. War is not fair, thus AH need not attempt to sim "fair"; however it does attempt it with the ENY calculations. Therefore it is equitable in a manner that would never have existed in a real war.
This is exactly what is being requested in such a situation.
Use a Spit5; take 2 kills, go home, get another, repeat until enemy defeated. 
Fly Luftwaffe.
190 A-8 = 31 (+/-) ENY
The issue isn't being able to up an airplane of choice, its implementing an ENY where applicable when two sides attack strictly the one side that already has an ENY restricting what it can fly.
There is no pilot that can take town 5 NIKS with a 190A8 when there is a horde as was mentioned here, so when the two sides that do not have the ENY attack en-mass on 1 side, there are little options to defend yourself with. There is just no match or anything to keep it even remotely close to fair.
I can assure you, I have never seen anyone up any of these planes to defend a base while its under attack unless an ENY is in place, A6M would be more appropriate for this type of defense, much less use them to attack a larger force, since in most cases they would get eaten alive by the 5-10 ENY planes easily.
So by relieving the ENY for the 1 side, or increasing it for the two attacking sides, or having an area ENY would more closely match the actual dynamics of the game.
When I come to your town, I surely don't see you practicing what you preach, and surely don't see you upping these planes to defend yourself, your wings would be clipped faster than you could say Foul.
