If there's an invisible barrier in spawn, then I haven't noticed it but agree it should be fixed.
I disagree that there should be flares available for a gunner in an attack helicopter, that should remain with the pilot, he's the one that decides when to use counter-measures and when to disengage from combat as a fall back option. If you mean that the gunner should also have flares, I disagree, you'd never be able to shoot anything down unless the flares' cooldown were nerfed, which I would prefer it weren't as you're not always flying around with a gunner but as a sole pilot at times. IMHO leave the flares alone.
I agree that DICE should bring back TV missiles for gunners of attack helicopters. They were fantastic to use, felt satisfying, and used active skillsets to hit or miss. This should be an option as an aircraft gunner perk/equipment. You could balance this by making it a very visible rocket so that enemies can attempt to actively dodge it that are in view of it, just like the G-84 TGM that operator Ewelina Lis was able to use in Battlefield 2042. It's speed would need to be trimmed as everything in Battlefield 6 feels slow.
The issue with AA (Stingers/Turrets/AA Tanks) is that they have a normal range (extremely high Y-Axis, medium X-Axis), but the maps are too small for that range, so they can cover almost the entire map. We never had these issues in past Battlefield titles because the maps were much larger, and the available air space within these maps was even greater (as was the ceiling if I recall).
They should remove the low-flying non-lock on aircraft as a baseline and make it an optional perk for aircraft in their equipment, but still prevent lock on with visual interference; trees, terrain, buildings, etc... This would provide some balance back with AA, but also promote skilled pilots abilities. Low flying aircraft are also in danger of ground attack like tank shells, RPGs, AA turrets, and small arms fire.