A quieter home network
Smart plugs, a printer, two consoles and a television that phones home every few minutes. None of them need to see my laptop, so they no longer can.
Three VLANs and a rule
A second-hand managed switch and the router I already had were enough. Trusted devices, guests and “things” each get their own network; the only rule is that the things may talk to the internet and nothing else.
The surprising part was how much calmer the logs became. Most of the chatter I had been ignoring was devices looking for each other.
What I would skip
Per-device firewall rules. They looked tidy on paper and were a pain to keep up to date. Coarse groups are easier to reason about.