Best way of dealing with this is that you have a number of battlelines that you can conquer, forcing other players to respawn further away, for both sides, if numerous enemies are too close (within LOS).
I have been advocating this before, but it should also be a game within the game, last defensive tank battleline is the hangars, and on the attacking side, when you run out of battle-lines you can not spawn there anymore. it should be a number of sides where you can attack a field from to make the attack more flexible, and only MBTs can make you lose attacking lines / count to the defensive line.
A tank radar bar should be a must in these battles, and please take away instant-repairs ,they make me think of Battlefield or other arcades.