I’ve had them for longer than the Shelly integration in hass existed so I’m using stock firmware and connect them to my MQTT server to avoid a cloud dependency. I haven’t tried the hass integration or flashing them, this is working fine for me.

The WiFi signal is mostly fine. There are cases where it takes a second or two to update on hass, but that could also be the MQTT server being slow. It doesn’t affect the operation of the lights since the Shelly’s are configured to switch the light themselves and not depend on hass to give them the command, that way the light still work normally if hass is down.

I have 6 Shelly’s installed like this and it really is a non-issue. If the light isn’t in the state I want, I flip the switch. I have no idea what orientation it’s in and I couldn’t care less. The same applies to my Wife and kids, nobody cares which direction is “on” and which is “off”. It’s pretty obvious if the light is on or off and if you want to change it, just flip it.