Helicopter fix idea: the real problem isn't damage, it's that helis are free and infinite. Suggestion:

• Helis aren't spawnable like ground vehicles — earn one via score threshold mid-match, squad-only for first 15s then open. Kills the spawn-rush and camping. Gunless transport stays freely available.
• Damage splits into hull (repairable, caps ~60%) and critical (unrepairable, builds slow), no more infinite life gunships.
• Critical damage = worse handling, damaged heli gets harder to fly, no on/off switch.
• AA gets real tracking assist but shares lock with stingers nearby == actually threatening, not a hard counter.
• Lock time (stinger + AA) scales with airspeed, hover = fast lock, moving = slow lock. Punishes nesting, rewards good flying.
• Attack heli doesn't spawn till ~3min in — early game stays ground based (or at least not attack heli based).
• Recent teamkills lock you out of aircraft (including transport sacrifice for attack heli).
• Transport comes in gun/no-gun variants, for map flexibility. Map variants without helicopter gunships possible.

Doesn't nerf the flight model, just makes helis earned, killable over time.