WWII helicopters might be interesting, but with so many more historically important WWII vehicles yet to be modeled, I would think helicopters are last priority for Aces High, particularly because they presumably would require such a disproportionate amount of developmental resources.
Before whirlies, would much rather see Pipers and Stinsons and Fiesler Storchs, flying boats, and continued addition of the many other air-sea-land vehicles that contributed the most to that era.