Welcome @lyonmaster!
Personally only seen one person do a Makita mod to integrate SuperPID. Seen a few add SSR/relays turn power Makita on/off. Some folks, that really want/need speed control, after spending some time with their machines, seem to end up using increasingly affordable VFD and Spindles. Most folks seem to just turn router/vac/air/etc… on and off by hand.
It’s neat being able to mod and upgrade parts over time on these CNCs.