Well, what if we made them into clusters, like the factories inside of the cities? Like by fighter class, country or make?
Curtiss Wright Factory:
P40
FockeWolf Factory:
190
Messerchmidt:
109, 262, 163
However, you will have ten planes by the make in reserve once the factory was destroyed. Like somebody destroys the factory there is a limit of 10 P-51s and if one gets shot down there will be nine and so on, but if it lands the score will stay the same.
I know this a way to get people to hord the planes, but I'm just putting in my 5 cents.