RedBaron had the start of this but never implemented it properly. There was a category of two seaters that were listed as 'attack planes" that were supposed to be flown more aggressively than their more stable cousins. Some ideas:
Aggressive 2 seaters:
Hannover CLII
Halberstadt CLII
Roland CII
Sopwith Strutter
These two seaters should fly aggressively (AI actively tries to bring forward gun to bear) when attacked. Otherwise they should go about their business.
Special cases:
Bristol F2b: Should often be flown as a fighter except no inverted manuevers. Depends on mission. Brisfits on two seater missions should use the same algorithm as other aggressive two seaters. However, brisfits on scout patrols should use scout algorithms (once again - no inverted
).
Fe2b: Needs some special AI due to pusher arrangement. Should be flown aggressively into 1916. By 1917 should be flown more like a standard two seater.
Standard two seaters
More or less everything else. These types should either run from fighter contact if outnumbered, or use close formation tactics for mutual support if the AI thinks it can bull it's way through. There needs to be some logic in place in the order of "can I complete my mission and survive?". If the formation starts taking losses they should abandon the mission and try to escape.
This also leads to an interesting discussion of scout AI. Scouts should try to attack two seaters from below. If scouts are attacking a formation of two seaters they should make passes and break off. They should not park behind the two seaters and get torn to pieces by the combined fire of the formation. Parking is OK if attacking a single plane. If the distinction is too hard to code I would prefer to see high speed passes implemented.
As usual, it all revolves around AI AI AI AI ... IMHO these things can be implemented. It just depends on how much effort is dedicated to this element of the game.