I've found a small color-changing LED that works with Tiny Whoop!
This comes with plenty of extra wire attached (4 inches) but when I cut the wires down to the length I like (maybe 2 inches) it weighs only 0.2 grams. Although this LED is made to work on 3 volts, I've been flying several of these using HV batteries and I've not had any issues with heat or early burnout. The colors change very slowly, taking about 45 seconds to cycle thru the colors of red, green, yellow, blue, cyan, pink, white, and back to red. It's not as bright as the headlights of course, but is brighter than the standard Tiny Whoop LEDs.