Yeah, this is why I like the Xiaomi Aqara HomeKit Gateway method so much. Honestly don't understand completely (I mean, I do a little) why anyone running Homebridge already wouldn't do this. It is, as you wrote "faultless" 
But what's really impressive is that the sensors stick to the Xiaomi Gateway like the tackiest glue I've ever touched. I was playing with Sense and my Aeon HEM recently, plus adding and additional HEM. Had to cut power many times over several days, plus we coincidentally had some unexpected power interruptions. Not a single sensor has dropped from the Xiaomi Gateway, or misbehaved in any way. The cost of this Gateway was $30 US, and now it on for $40 US. That's often the cost of one good sensor (and sometimes the cost of one bad sensor too).
If I could use Hubconnect to link it to HE I would get one and do as you suggest.
Has to be HomeKit. That's the only link between them at the moment. It's the safest one too, since they do force a connection to Chinese servers for their regular Mi Home app, but for HomeKit, the Aqara Home app can be used. They force a connection to the internet to setup the WiFi, but once you do that, you can block them and it still works locally with HomeKit.
you could stick one in your letterbox.....
Ok.. so some early feedback on the motion sensor. It may not be as sensitive.
I replaced the Orvibo I had in my office. I used it to drive a couple rules, if there is no motion for 15 minutes then shut off the lights and kill the heater when I leave the room.
With the Xiaomi in place this morning.. My lights have switched of 3 times - I haven't left the room at all.
Admittedly I am just sitting at my desk, working on the computer, so it could be considered subtle movement.. but compared to the Orvibo/LivingSmart the Xiaomi is not working for this application.
Not sure the reset time on the Orvibo, but the Xiaomi are fixed in hardware at 1 minute. So if you're moving during that minute, nothing will happen. True that they are not as sensitive as many others. You need multiple to cover a moderately sized area.
You can lower their reaction time with a fairly simply hack, but it only works on HE. The motion sensors that I later moved to the Aqara Gateway had to have the "hack" removed, because they will not work with the Aqara Gateway when the hack is in place.
Yes, I had seen the hacks for the reaction or refresh time, and there is an option in the device settings with the driver... but since I have my rule set for 15 minutes delay, that tells me that it's not detecting anything over that 15 minute period... assuming it refreshes/updates every minute.
Looking at the events log for the device should show the sensor going active/inactive.
Might be worth a look to confirm your suspicions.
They never go inactive on their own in HE, so @veeceeoh wrote the driver to change them to inactive after a user adjustable timeout period. The hardware hack shortens the time when they will start detecting again, rather than when they will switch to inactive.
So while you could set the reset time to 5 seconds in the driver, no detection would occur
until 1 minutes has elapsed (unless they have the hack).
I've no idea how far it is from you, or if you're actually a ghost , but this sounds like you may have a bad device pairing, They're not THAT insensitive. Somethings wrong. I agree, check the live logs and past logs.
Oh, and if you decide to try more, as I noted before, for some reason I have much better luck with the Xiaomi Mijia Motion Sensors staying paired directly to HE, than the Xiaomi Aqara Motion Sensors.
I have found that all my problems stopped when I put all my Aqara's on ST and all my Mijia's on HE
Interesting. They are not standard, that's for sure.
OK. Just checked the xiaomi motion sensor that I left alone after the power cut and according to the event logs it checked in 6 hours later and is reporting motion again.
This is good in one respect that if we are away and there is a power cut, the devices will come back.
Before people comment, , yes I know I should probably get myself some sort of UPS.
Let the search begin. 
I'm not gonna hate on you for not having a ups. They're somewhat of a pain anyway. I'll just send someone to my house to straighten it back out. Ha!
Ok so is Homebridge working again with IOS 13 maybe, because I had it working when I was on IOS 11 upgraded to IOS 12 and I could never get it to find my homebridge instance.
It works. Never stopped. Did you mean to post this in the Homebridge thread, or was this in response to my post about using Homebridge and HomeKit with a Xiaomi Gateway?
Yes it was in response to this thread if you google it and maybe even some on here have had the problem Apple did something that broke the connection in IOS 12 where as the Homebridge instance wouldn’t be found on the network I can confirm that it was broke for some because when I upgraded my iPad my wife did not and my son hadn’t yet upgraded his iPhone 7 my iPad could not find my hombridge server bu6 my wife’s iPad and my sons iPhone could then my son upgraded his iPhone and then he couldn’t connect and as of this day I’m still on IOS 12 still can’t connect but my wife’s iPad on IOS eleven can they why we haven’t upgraded hers as of yet.
I see. I don’t recall ever experiencing an issue, but I’m in the beta stream, so maybe it was fixed before I experience the issue on 12.
Yeah I mean I was really pissed but not surprised Apple just always break things when the come out with updates. It took me a day and a half to narrow it down to the fact that it was the update. The specific version of Homebridge I use is called Hoobs it’s the easiest way to get a Homebridge server running after hours of trying to figure it out I reached out to them and they confirmed it was the update because they had already started getting error complaints, they said until they could narrow down the issue they said stay on IOS eleven on one device so I haven’t updated my wife’s iPad to keep things running.Im going to be updating to IOS 13 on my iPad in the coming days to see if I can get it working again on my iPad.
Had a look at the logs as well as keeping the device page open for a bit to note when it went active and not... it wasn't picking up the more subtle motions...
Relocated to a new spot in the room and it worked well. Moved back to the original, where the Orvbio had been previous, and same poor behaviour. So back to the new spot and we're all good.
Its like they say "Location, Location, Location"
Any update on this? My iPhone is currently 13.2.3 and just about to try Homebridge.
