Setting up QoS rules for household?

Has anyone here set-up quality-of-service rules on their router for the house? How did you go about prioritizing different services / devices, and how well did it work out for you? Did the de-prioritized services take a noticeable hit?

I'd like to deprioritize my Nest cams...I have them set to their maximum quality at the moment, but it's not important that they continue maximizing bandwidth when there's something else happening on my home network.