Hello there.
Suggestion is to improve planes damage model to match current standard for other types of vehicles. I know ArmA is not a flight sim game, but airplane DM feels over-simplified, with "HULL" damage only. Engine and fuel damage should be possible, too, so the player would be forced to land or even crash-land. Gear damage could make things much more interesting, if only planes didn't crash into a huge fireball when trying to belly-land.
The DM doesn't have to be visual, even if it was just logical it'd be good. No change is required to the flight model, although if damage influenced how the plane flies it would be really good.
I'm sure you can figure something out, unless this mean old engine doesn't allow you to. I'm really crossing my fingers here, cheers!