AnEejit I agree with you that ideally having 5 classes would be the best solution.
Regarding Support, I also agree with your point, and that’s exactly why I think introducing a separate Medic class would be a great improvement. The Medic could be fully focused on teamplay, with gadgets like defibrillators, med packs, and smoke grenades, and carbines as their signature weapons.
On the other hand, Support could return to a more classic Battlefield role, focused on sustained fire and area control. For example, giving them ammo crates, mortars, an interception system, C4, incendiary grenades, and LMGs as their signature weapons. This would make Support feel much closer to how it played in older Battlefield titles.
I also understand your point about Assault being too solo-oriented right now. The idea of an explosives crate could actually be a really good addition. It would give Assault more tactical value and a bit more teamplay potential, instead of being purely focused on aggressive solo gameplay.