Ups and Downs..

First off I want to start by congratulating the BF team for turning around what was a sorry time for the franchise. It seems like the higher-ups listened more fervently to player feedback than other releases. With that being said, I think there are improvements to be made:

Visibility

Enemy visibility difficult to ascertain
Large red diamonds are not the answer
Players want a sense of tactical stealth in realistic squad based shooters. They do not want to find good cover only for the game to point out players with red diamonds before they're even seen by the player. This ruins immersion and will lead to more "cod" style firefights of running, jumping and shooting. Myself and many others' experience in the beta was that this marking system highlighted players before we saw them move. This feels unfair for both sides.
An improvement would be a 3-5 second delay for the red diamond to appear. You could also increase visibility of player models, or require players to press a tag button for the diamond to appear.
Camouflage could be amended to have slightly more shine against environmental textures to improve visibility.

Classes

A return to classic BF classes was a must to distinguish the franchise from other shooters. The fact CoD has seen such a loss of player count and is constantly ridiculed is for its lean into "meme" characters and models.
With that being said, the identity of each class still does not feel fully established. Whilst it had it's flaws, the BF5 class system I think struck a perfect balance of gadget and weapon availability and speciality. Assault should carry the high-explosive anti-vehicle weaponry, support should carry the ammo packs, placeable shields and turrets whilst carrying LMGs and shotguns, medics should carry the small SMGs and provide medic bags, whilst recon carry small silenced SMGs and sniper rifles, whilst retaining the spawn point gadget.
Creating a distinct "occupation" for each class allows for proper balancing to achieve a games target objectives (obviously all can be changed in portal)

Maps

Although we only had a small taste of maps in this beta, and all were very well balanced, all lacked any significant events that changed the map i.e. BF4s Siege of Shanghai
Such maps define the Battlefield experience, and why many long-term fans look back at previous titles (mainly BF3 + 4) with such reverence
Expectations are that such maps will be available at release

Lighting

An improvement to 2042, though effects such as variable contrast for entering buildings is more of a hindrance than a copy of realism. Whilst obviously walking into a dark room from the outside, your eyes need to adjust, this poorly translates to video games and should be toned down. Many games do not employ this feature, and i never see it high in requests.
Players just want impressive particle and explosion effects that mimic the high-intensity of modern warfare. Next-generation effects trying to mimic real-world eye adjustments are unnecessary.