I haven't implemented much but I'm planning on going with Shelly smart relays. I'm not a big fan of smart bulbs and stuff. I don't know if that's mostly what you mean by Wiz.

I was checking home assistant out and it seems to have quite a lot of things integrated so at least we aren't slaves to their apps, even though it's always connected to their servers.

Wouldn't trust any IoT device that connects via Wifi.

Don't forget the "S" in IoT stands for Security.

IoT devices focus on as many features as possible, for a as low as possible price. Security is always an after thought.

They are meant to fit in the back of a light switch so are very tight on space. I opened one up, it's not very complicated but the routing is probably a bitch.

I actually know how to make PCBs and 3d print cases and stuff. I have 2 printer (I barely use them though). That being said, it is using main and if it fucks up and something catches fire, I think insurance companies wouldn't pay out. I don't think its worth it, but I did legit look into it and have like 2 half prototypes in kicad lol.

But ya, I don't know. I don't really want to touch stuff that doesn't just run on a small battery or off USB. Simple mistakes can snowball fast with higher voltages.