So I fly RC planes as a hobby, and I really love it. I recently made a 3D plane that could hover right in front of me and I thought that was the coolest thing ever. I tried to re-create the plane in simpleplanes and I was unable to do it because airflow over surfaces is directly related to airspeed, and has no relation to whether air is being pushed on it by a propeller. I think it would be awesome if some sort of prop-wash was put in place. It could make air powered boats possible, or small propeller powered vtol craft. I have no idea how such a system would be implemented, but any system would be cool.