This part of forum (from your link) isn't for "normal" user
I can't see it.
Let me explain here.
Yes, there are other ways to monitor the voltage, but:
- BT range is small and requires a tablet (hands or pockets and looking at it) (I "using" my wife for it
)
- 3dr - ok, but it is an additional transmitter in the model and its impact was found on a compass
- By telemetry, but eg. futaba r7008sb is not (I hope for now) supported and it requires an additional connection (doubled)
- Via OSD - ok, but not everyone needs to use it
Signalling is already implemented, very good and praise you for it. However, I know from experience that not every moment can be seen and heard.
I suggest a compromise.
Like you said: stage 1 (first level) - only signaling, nothing happens
stage 2 - stop, hold position and landing.
I think that the slow landing (even in a place undesirable) is safer (see and hear copter, the environment can react) than copter like a stone falling from the sky.