Hello @heggink,
Interesting proposal
You asked:
Has anyone looked at this?
Not from this point of view.
I looked at the possibilities of using my Google Home Mini or Nest Hub for other tasks, such as detecting sounds, custom messages, etc.
Anyone interested to collectively give it a go?
Yes.
It lists OpenHAB integration although that seemed too scripted for me (unlike the HASS integration).
I have no experience with OpenHab or Home Assistant.
Normally I use Node-RED for any scripting and so far I have achieved everything, I needed and push the values by MQTT to Domoticz
For some of the tools, you mentioned, Node-RED has already custom nodes available.
Let me know about your thoughts.
Regards