Encourage alternate play-styles

We are familiar with the meta play-style of bouncing around with a DRS-IAR, smoke grenades, and medkits strictly for self-use, but a wide game like Battlefield should encourage some other team-oriented play-styles. With the weapon sling and the injector, it seemed like Assault was going to be the lone wolf Doomguy class, but that didn't work out well. It's fine to have one class for that play-style. But let's look at the other non-vehicle types of play:

Fire support. Press Mount to get sniped. The combat medic perks are actually more useful for this role (stronger shield, better projectile catchers, faster drag revive when you have to do it).
Sniper: Hang back and effortlessly 3D spot anyone trying to flank. Snipers who erratically weave with a Violet Laser are far stronger than the one who lies prone in a bush with a bipod, for some reason. It might make more balance sense to keep them powerful, remove scope glint, and make them less mobile unless using an aggressive gun like the Scout.
Spec Ops: Footstep silence perk has been nerfed too much, other perks are useless. There are no commander assets to disable. Snipers and mortars can't be assassinated that are deep in the HQ zone. Better to go Assault and use the spawn beacon and ladder.
Medic: Press E to pick up kit by accident.
Combat engineer: Cooldown perk has been nerfed. Removes challenge by auto-spotting mines (this was added when the auto-heal during idle was universalised). Can't fortify. Vehicle supply crate heavily nerfed.

There has to be some other objective than killing in this game for different play-styles to emerge. Every mode is almost TDM. In BF2142, you could use a Spec Ops cloaking device to help get you in to the HQ zone (that was not out of bounds then) to harass the player in the commander role. Destroy his assets or make it so he can't singularly focus on commanding. I hear that in BFV you could build fortifications. In other games, there is some kind of buff given to a mounted LMG that makes it a defensible point instead of a sitting duck. There can be stages to vehicle damage that aren't purely a health bar, introducing the possibility of engineer gadgets that destroy tracks, blind optics, slow traversal, etc. Give the Spec Ops role a shorter animation for knife kills (no looking at the dog tag) and remove the limb damage multiplier applied to the throwing knife. Squad members should only spawn on the leader or a beacon.