I can imagine the pain soldering the single key pcbs and then wiring them. I think if i did another build, i would skip the per key LEDs entirely…
Trackball is pretty good. The sensor and PCB are great and it i like the position now that i have gotten used to it. The ball bearings are not perfect, but go a long way. Maybe one day i will look into BTUs. There is a mod that uses a trackpad instead, which i would be willing to try out of sheer cusiosity.