A few other things to be aware of:
Parcel security is only effective to 50 M above the terrain surface for people not explicitly banned by name and only to 800 Meters if you do ban them by name. So a stranger you haven't banned before could still enter your parcel's air space at 51 M above the terrain, or a banned person at 801 M altitude, and look down at you from above, even if you turn on 'parcel privacy', since once they are in the same parcel, at any altitude, they can see you just fine.
To prevent that you would have to place security orbs in your airspace so the 96M radius scanning range of each orb overlapped enough to cover every possible altitude. Then set the orbs to ban intruders by name and eject them, based on the parcel settings. Make sure the security devices limit their activity to the parcel boundaries, and to give sufficient warning time to allow an innocent flyer to pass through unmollested.
