We have found that flying across a slope ends up using less waypoints and executes faster that flying up and down the slope a bunch of times.
DJI aircraft hold 100 waypoints so you can't take off with more than that loaded. In almost all cases this is plenty because you run out of battery first but in the case where the terrain is super rugged it will likely need to come back and get more waypoints early.
More rugged sections of the survey area will burn through the waypoints more quickly. You can see the locations of the waypoints on the blue line in the Terrain plot.
The P4P and P4Pv2 have the same parameters for the camera so the flight spacing would all be the same. When the aircraft connects it will override what ever is set in the Settings. The aircraft/camera that is selected in the Settings is used when doing offline planning without an aircraft/camera connected.