Hello 
I know I’m off on the request because of the lack of autopilot, but if the “sightseeing” part is important, I can’t go without recommending the Optica, either by Orbx or by Got Friends (Marketplace only, i think).
It’s a plane litteraly made for sightseeing, it flies very stable, have the best view you’ll ever have in a plane.
But no autopilot 