Just added some Xiaomi sensors to my Home Assistant setup. Got a CC2531 receiver flashed, so far got a couple of the temp/humidity sensors, door sensor and a motion sensor.
Added some GU10 Hue bulbs to the bathroom, the motion sensor is set up to trigger the lights on at a different brightness depending on time of day and also triggers below a certain Lux level during the day. Added the door contact sensor to this as well to keep the lights on as long as the door is shut, to avoid the lights going off automatically (after 60 seconds) while having a bath/shower etc.
Just about to order some Aqara smart buttons for a few functions. One of which is to use one as a smart doorbell. I have set up Home Assistant to make an announcement via various Echo's around the house, and also to push a notification to our phones along with a snapshot from the Unifi camera pointing at the door.
I've got an aqara smart button switch on the way. Whilst the missus loves the smart lighting, she does get a bit annoyed that if she wants to turn the main light on in the bedroom then she's gotta open up the app.
My plan is to test it works flawlessly with Home Assistant just for that room, and then I can buy them for every main light in each room. I've got hue dimmer switches, but to kit out every room would be expensive, whereas these are only about £5 each.