While this is an excellent idea, a better idea might be to give those things a hold-fire ability that will also prevent automatic rotation. Having all 3 abilities (prioritise vehicles, hold fire and handbreak) would be very messy.
Polluting the interface with things means it will be more difficult to convince for the need to add further QoL changes later on.
i think just hold fire is enough. free fire or hold fire. of course target lock should be possible with hold fire unlike now - as in sherman dozer in hold fire if ordered to attack a bunker will forge that order if you move it etc etc.