Well I have not blown up any VESC so far.
I think setting adequate (supplier recommended) Maximum Current for Battery & Motor should prevent any big damage.
Also, software-wise, set Maximum duty-cycle around 0.95. If you set it to 1.0, program will be unstable, and (in theory) the mosfets that get stuck being ON can draw too much current and burn out. Causing battery short, which in your case will be prevented by the Fuse(that’s massive).
Those are the 2 tips I remember being posted from people who had their VESCs blown.
About ‘safety’, hmm… I don’t have a good idea. Since VESC already has setting to ‘ignore’ PPM value if wrong inputs are made for certain period of time. So if you have PPM signal disconnected, VESC would stop the motors(I just tested it and it does).
So I think if you set up critical VESC settings properly, any BIG(Fire, Explosion, Surf-board running away from you) Problems would not happen .
Nice Fiberglass job by the way! is your job related to FRP, or did you learn it to make stuff?