As far as “just works” get something that is directly integrated with home assistant and IMO if home assistant has direct access to the radio or method of communication, the better. As others have said both Zigbee and ZWave devices can interact directly with HA using a dongle and I do so with a VM on Proxmox and it works great, I do however think the ZWave JS and ZWave JS UI integrations are far and ahead of Zigbee ZHA integration (I won’t speak on Zigbee2MQTT as I don’t use it)

Wi-Fi devices are nifty but their reliance on the strength of your WiFI, internet connectivity, DHCP working, IPv6 support make them more variable than the ZWave and Zigbee standards that really just require you build a good mesh by having devices every so often that each other can “relay” through.

To me this sounds like you’re missing another service to monitor your internet for uptime. I recommend Uptime-Kuma.

JK. Best part of the self hosted media server is I can usually get away with updating and rebooting the firewall while the wife is watching her shows and she’s never the wiser!