Things to improve / add to Battlefield 6 from my perspective as a BF vet :)

Additions to Multiplayer

Future maps should be large scale to emulate that sandbox experience.
More unique maps with unique assets. Like in BF4 each map is very different from one another. Can we get a snow, jungle, island, underground map. I feel like majority of the maps now are just me fighting in construction sights.
Implementing small scale levoluation such as interactive bollards, shutter gates, light switches, gas pipes, elevators
More unique Dog Tags and Vehicle stickers (I believe stickers/dog tags could be outlandish since it isnt up in your face when playing)
Gold or any rare earth mineral with signature designs camo for weapons as a mastery camo, think BF1 rare skins on weapons. In addition maybe foliage on weapons would be great too.
Hinted in a blog post but Navel Combat and Little Bird would be great.
Cant fling vehicles into the air with c4. It really is a battlefield staple
Optic sight customisation. Like colors, size and opacity. We could also add Black Ops 2 optic customisation too with unique optic sight besides a dot.
BF1 type operation game mode. Since there are two maps from each location, it would be great to get a story type operation mode spanning through two maps.
Funny/Creative easter eggs like the megalodon or plant vs zombie figure on a map.
Platoons
Persistent servers to keep the same players in the same lobby after each match.

Fixes for Multiplayer

Vehicles are too much of a glass cannon es with engineers with two offensive gadgets. For LAV you could reduce splash damage for increased mobility.
Helicopter physics rework. They seem too heavy and floaty. Still good but just not right
Helicopter need more defensive measures
RPG velocity seems to be too high.
Vehicles especially air vehicles gadgets not working properly (air radar)
Flares dont work when air vehicles are painted leading to one shot kills
Weapon Bloom tweaks
Terrain geometry causing solider to fling into the air
I believe the sniper sweet spot should be removed or nerfed in terms of range
Breakthrough & Rush rework
Lighting/Sun fixing when transitioning to dark to light or light to dark.
Progression rework

Class Rework

I believe Support is too overpowered with having both ammo and health while underutilised Assault doesnt have much to offer. The best way to rework this imo would be to give assault ammo while letting support having heals.
Engineers are in a good spot but having both mines and rockets could be detrimental in the survivability of vehicles.
Recon needs a small bit of love in gadget the department but i dont know what exactly.
Grenades might need to be reallocated to different classes for balancing

Battlefield Portal/Community