Hello Peter. A great video, thanks. I film all my flights with a GoPro from inside the cabin of my Foxbat but I can rotate it to point at the most interesting parts of the flight. I love the apre flying when I playback my flight in the comfort of my own home. I will often produce a DVD for some of my passengers, edited to include the highlights and with music added to remind them of their flight.
One thing I was keen on was to ensure the ambient sounds as well as intercom transmissions were captured to give the videos context. I built a mixer that resolved all the audio inputs into one. You can see my latest results here :- (no music) https://www.youtube.com/watch?v=KEshdhGwZ4c Solent Radar ATC Zone Transit on YouTube.
I have just figured a way of mounting the GoPro externally and employed a drone mount to avoid the "jellow effect" caused by vibration that distorts images captured by a rolling shutter device. I look forward to some external filming from outside the cabin. I was impressed by the smoothness of your capture and wonder what mount you used?