Small vehicles need some means to defend themselves when parked on a planet.
The most obvious option is to allow HV turrets to be placed on SVs. I can only guess why this is not currently the case. Perhaps auto-aiming weapons would make SVs overpowered? If so, I would suggest having the turrets unable to fire while the SV is moving (vehicles already prevent the player from exiting when the vehicle is moving, so using the same detection to disable/enable the turrets shouldn't be difficult)....
Small Vehicle defenses
The most obvious option is to allow HV turrets to be placed on SVs. I can only guess why this is not currently the case. Perhaps auto-aiming weapons would make SVs overpowered? If so, I would suggest having the turrets unable to fire while the SV is moving (vehicles already prevent the player from exiting when the vehicle is moving, so using the same detection to disable/enable the turrets shouldn't be difficult)....
Small Vehicle defenses