True, the planet's occupants are quite safe, but any orbiting habitats and satellites wouldn't be. Overshooting would be a good idea, but dropping the rings which would be a good 2/3rds of the vessel's mass would still be prudent for intrasystem mobility. Think of it like a semi truck dropping its trailer. Strictly speaking it doesn't *have to* pop up, but it's there to keep the designers happy. The ship's core is basically just a big can with a couple windows and some ring support pylons. Engineers like to put little flourishes in designs and the least I could do is give them a bridge module that elevates 4 feet to give an outside view to the bridge crew. In a battle situation, it goes back down and the bridge egress lift locks out in the event of an intruder alert. By the way, the lift is added security due to it being the only way in or out. Also, in the event of an emergency, the bridge module can eject and keep the bridge crew alive long enough to dock with a shuttle. As for the rings that are left behind, I thought about leaving them under computer control or having a minimal crew stay behind in a pod just in case they need to be moved. Maybe a computer can be trusted to move it to where it's asked, but if hostiles are around, I wouldn't want to park my car with the windows down and the keys in it. So, if needed, a habitat/control pod will drop from the center ring on a scissored pylon that will sustain a small engineering crew for 2 weeks. This pod will be about twice the size of a large tour bus and will get its power from the shuttle that docks with it. This shuttle will also be the source of power for the rings while the ship is away. Obviously the range of this situation will be limited but it should be sufficient to get out of harm's way. But usually, in a non-hostile situation, the pod's computer can handle monitoring and stationkeeping duties.