I think for a first pass we’ll try a combo of intensity and color change. I’ll add a Teensy to the belt and wire up half RGB leds and half Blue leds. The RGBs and blues will both be off in between 450 and 350 since the zero rotation value seems to be 400, ignoring the filter’s charge/discharge curves. Once the rate of spin exceed these values, on either side I will begin ramping up the intensity of the blue leds proportionately to rate of spin. The RGBs in contrast will have (relatively) constant intensity but will change color proportionately to the rate of spin and the spin direction. The color at 450 and 350 will be yellow-green. However, as the rate of spin increases toward zero, the color will shift to the red. As the rate of spin increases above 450 the color will shift toward violet.
I’ll put switches on the belt to allow me to select between RGBs and the Blues so that we can see what looks best.