It would be nice when using FPV mode if you could (optionally) have a second small PiP (picture in picture) which would show you the Line of Sight view

Thanks for the suggestion, I will investigate the possibility for that.

I've implemented extra view points using opengl and java and initially thought it would be crazy hard to do, (but in fact was dead easy!) I bet on Unity there are LOADS of example (rear view mirrors etc)