The Line Of Sight image (LOS) has nothing to do with the POI flight path success. The P3 autopilot computer is flying a perfect circle at the exact radius, altitude and speed you set, and the camera keeps panning and stays pointed at the POI you set first. If the POI gets visually blocked for a while, the P3 will just keep circling until you take control and stop it.
I am pretty sure a loss of signal to the controller would initiate a RTH automatically, but I'll give it a try next flight.
Waypoint feature is a lot less useful than the last version on the P2, which was pretty impressive. Maybe a new pre-programmed Waypoint feature is planned, it should be pretty easy. Then need to include altitude changes, speed changes and camera angle 0 degrees to 359 degrees from 12 course line. They should also allow you to specify the tilt down angle on the camera for each leg. -90 degrees to plus 30 degrees. They may want to include a pause, rotate at a selectable rate, with camera tilt angle, then continue again. Ideal for farmers or ranchers to inspect their property. Also ideal for police search or investigate operations.