I don’t think an additional UPS is really necessary here. I do have switches to other parts of my network, but they’re just for TVs and game consoles, so I don’t really think a UPS is needed there.
It’s mostly a failsafe so I can poweroff my NAS properly rather than corrupting data. Since my server and router are on the same power strip, it makes sense that they’re all on the UPS since they’re the 3 main items interacting with each other.
Something with NUT as [email protected] mentioned might be a good option so it can send alerts when it’s activated. I’ll have to research that more.