If you want to use non-HomeKit items, you can use a RaspberryPi and run HomeBridge. Or you can just stick to HomeKit items (which are unfortunately more expensive and limited in selection).
I see you’re mostly unsatisfied with voice controls, but Siri is pretty good with HoneKit controls. Or you could just use your phone.
This article is paywalled, but put to rest the “why is Siri so bad still?” question for me. [1]
One of the details reported I found most compelling was that internal dissatisfaction w Siri’s ability is so great that the headset team seriously considered using an entirely new / different voice system for its product.
[1] https://www.theinformation.com/articles/apples-siri-chief-st...
Google Home has its share of issues, but Assistant and Siri don’t exist in the same universe. Siri is just kinda sad tbh.