This is really hard.
Personally I hate crap a/c (read: pre 1942), and I love carrier missions (from the time when they replaced the Wildcat).
To add to the period we could use a couple of French aircrafts (Dewoitine D. 520 (only 50 served during the battle of France) & Morane) and a map based on current Channel map to the north and to the east so we can simulate the battle of France. Most of the aircrafts are allready there.
If we want to go forward we should think about the British strikes into the occupied France: We should get the Whirlwind Mk. I (with the notoriously unreliable perigrine engines), the Spitfire Mk. IIb, Vb, Beaufighter Mk. Ic and Fw190A-1 and A-2 and the Bf109F-2, F-2B, F-4, F-4B.
Whirlwind Mk. I
If we are going East we need the Rata (I-16), I-153, MIG-3.
But irt would be nice if reliability issues on the aircrafts was modelled as well.
Maybe we should as for a "Reliability issue off" in the Realisme settings
