My concern would be radio link. Landing however far away you would be and let’s say 1000 feet higher than takeoff point, line of sight to ac may not be adequate. May not be fun trudging up some mountain trying to find your ac that can’t communicate with your rc.
I don't understand your point here.
The RC signal is not going to be any different at that height to if you had the height restriction removed and flew up the mountain.
I thought this post was about removing height limitation.