Nerf the Helicopter stability to reduce extreme/unrealistic acrobatic flight. Little Birds now have enough firepower to destroy tanks and are able to fly in unrealistic ways that decrease immersion and fun-levels for those on the ground. They should be stable when flying level but the pilots should need to constantly manage that stability or risk losing control of the aircraft. High difficulty maneuvers should be technically possible, but they should be highly difficult and should carry enough risk to make pilots think twice. Fly crazy and the forces from that maneuver should be difficult to overcome. This would drive a change in helicopter tactics that would rebalance the ground to air equation. Maybe they can stall? Maybe the g-forces become too powerful for the pilot to correct. Maybe both?