Ok, I know a WWII mod is out of the question, but what about one focussing entirely on the Eastern Front? Putting planes as strat map pieces should work for the Eastern Front, same with naval battles. Plus it was one helluva epic war, tanks, all sorts of diff infantry types, like snipers, Russian Marines, Volkstuurms, Partisans, Cossack cavalry, etc.
Factions:
The Soviet Union
The Third Reich
Finland
Hungary
This is just an IDEA, I dont have the time or ability to do it, but I'm just wondering how doable it is and I'm hoping someone may come along and take this up.