Almost all or not to say the majority of The fights started previously with a vehicular troop mobilization, so there is no better way to enter the battle than through vehicles from respawn points. The logic is simple:
Everyone starts out in a vehicle, or they might have the option to select the vehicle they want to use or the main spawn point on the map. Spawn points always accompany the vehicle while it is moving. You can only respawn in a moving vehicle if the vehicle still has enough seats. Otherwise it will appear blocked.
If the vehicle is destroyed it cannot be used to respawn. After being destroyed, its remains will disappear after a while. (To save CPU resources).
The vehicle will be restored to the base location and will be available for use again.
Postscript: You could optionally completely disable the ability of engineers to create respawn points.
It would be nice if that were added, but if armored vehicles that also serve as respawn points were suddenly added to the current game design, it might give too much of an advantage to the attackers.
Imagine, if you park an armored vehicle near a CP, from which an endless stream of soldiers will boil over, one or two AT soldiers may not be able to handle the MG42 sweep and the rush of attackers. By the time you call in the tanks and aircraft, the CP may be overrun.
Perhaps the entire game system needs more tweaking to add armored vehicles with spawn capabilities.
Or add a game mode where there is no problem with the appearance of such vehicles.
In the case of armored vehicles, you would have an area from the base where you can still be selected to respawn, after leaving that area, there is simply no way to reappear inside the armored vehicle. So for the replacement you must move to the armored vehicle and address it personally.
