I think War Thunder should add light military combat vehicles instead of only focusing on tanks, ships, and aircraft. Vehicles like Humvees with mounted .50 cals, armed scout vehicles, fast attack vehicles, and other lightweight combat platforms would fit modern warfare really well.
These vehicles are historically used in many conflicts and could bring faster gameplay, recon roles, ambush tactics, and more mobility compared to heavy tanks.
A modern light-vehicle mode could make the game feel fresh while still staying military-focused.