...and to make it worse, has anyone checked how many of us roboteers are colourblind? Green LED you live... red your ****ed. What about those of us that cant tell the difference?

Suggestion 1 (could be tricky):

Red (flashing or constant) = link in (required)
Yellow = weapon controller live
Blue = drive controller live
Buzzer = fault (failsafe failure, etc)

Suggestion 2 (slightly more simple):

Label your LEDs