I have no particular problem with early war aircraft, I do have an observation as regards
timeframe. With the Polish and French birds you are talking about a scenario life of about 2-3
months. With the notable exception of P-36/H75 hawks which were used in other theaters
after France's surrender.
Hmm... You got a point, maybe polish airplanes are a bit out of place since they were outclassed by 1939. But, having dutch, french (god forbid... the Gloster gladiator for the Belgiams), against early german planes, you could create scenarios for those planes for that period. Just because the French Air Force was badly organized at the time, doesn't mean that they didn't have good planes. Someone could create a scenario where the Dutch, British, Belgiams and French coordinate their operations (not very historical, fair enough) but it could be a good scenario. Remember that for a period of over six months, the two forces just stared at each other... what if the allies went on the offensive?

Also, Dutch and French planes have a good chance in an arena that is limited to early planes.
Also, there were "actions" between french and american force in operation "torch"... there is another scenario. And of the hawks were used by other countries, one more reason to add it for scenario purposes.