What I always missed in IL2 were the ground spotters. This was an intergral part of the 'Home Chain' in BoB.
It could be implemented by having a radio truck, with a certain 'visual radius', so that any a/c entering this radius will appear on the map and then dissapear on exiting the said radius. This would simulate ground to air comms of a/c in the vacinity and encourage map builders to place these radio trucks.
This'll work for both sides and destroying one of these vehicles creates a gap in the defence.
Keh!!!