I have a theoretically minor improvement for SHM that could significantly improve the perception of reliability (and increase my xAF).
I’m actually generally happy with the security portion of SHM except for the false alarms we’ve had. Most of these have been easy to identify because the ST multisensors have acceleration and contact outputs. All of my false alarms have been due to an “opened” door or window that hadn’t accelerated…
So my solution would be to include an option for multiple simultaneous points begore triggering an alarm. This could be s sensitivity setting (ie. User selects a threshold of  so that any cimbination requires an open and a motion or open and acceleration.
You can do this now by using Mike Maxwell’s zone manager. This allows you to create a virtual device which represents zone and then assign multiple sensors to it. He created it for exactly this reason, to reduce the number of false alarms by requiring multiple sensors to trigger and alert.
If you haven’t used custom code in smart things before, here’s the FAQ for that. It’s pretty straightforward, you’re basically going to copy someone else’s code and paste it into your own account.
If after reading that, you think it’s something you’d like to try, you can find Mike’s zone manager code by checking under “sensors” in the quick browse lists for smartapps in the community – created wiki.
Darn, I tried ZMM, but it relies on motion sensors as the second point to activate the zone, and doesn’t appear to use acceleration at all. Looks like I may have to move towards a custom option, or modifying the device handler…
So then you need another Mike Maxwell contribution-- The universal virtual device type. This allows you to have one device report as a different device class. So you can have a contact sensor report as a motion sensor, etc. and acceleration is one of the options.
That way you can make any of your other sensors look like a motion sensor and use them with the zone manager.
It’s a little bit complicated because you actually have to use another smart app to act as a man in the middle, but most people just use smart lighting. So acceleration is detected, it turns on the Udth virtual device which then acts as a motion sensor and the Udth motion sensor gets picked up by zone manager.
@Mike_Maxwell might have another suggestion, but that would be my next thought.
And I agree all of this would be way simpler if the official features allowed you to include zones of multiple sensor types. But since they don’t, the community is usually able to come up with a way to accomplish desirable use cases, it’s just sometimes it takes a few steps.