Problem with formation flying in AH is that in the game you can't control your position at the side of your leader by your peripheral vision. It makes formations like a classic finger 4 very hard to maintain, and even if you mannage to create this formation in flight, it is unstable, and takes too much attention to maintain. So in AH, formation flying turns into flying in "trains", where all the wingmans shall have leaders in their direct view.
My suggestions:
1) Add a formation "autopilot". Pilot has a ".leader" command. Pilot chose their leader, then hit "formation autopilot" button, which place him into the correct position at the side of leader, and this position is maintained by the autopilot till autopilot is switched off.
To prevent gamey use of this fuction is shall work only at short distances, for example .5k, and it shall break when leader makes battle moves (splits, breaks, hard turns etc), so it work only in pre-engagement situations, when this formation needed to cover each other 6th etc. In a battle it will not help.
It shall work as all other autopilots in AH. If pilots moves stick, autopilots is switched off. Only difference is that when autopilots is switched off due to leader move, his wingman shall be switched from "formation autopilot" to "level autopilot".
2) Add side screen icons which shows distance to the leader and direction to him (like in Rowans "Battle of Britain"). Also shall work only at close distances.
I think 1st way will be better.
Additionally it may be added a ".formation" command for leader, who can set distance between planes in formation, and (may be) even a type of formation himself (where to place his wingman, left or right).
It may be some way also to set formation not only for pair, but for a wing also. Apart from the apparent game advantages of such thing, it also will add to the visual and immersion side of a game. Imagine seing finger 4 fighter formation at the escort over the formation of bombers.
I understand, that for many AH players this feature is not needed, but people who flew scenarios will understand the need for such thing. Specially considering that AH2: TOD will be around some day.
Just ideas. Will apreciate your comments.