Hi Will
The eaton stuff might be a good place to look
https://www.eaton.com/gb/en-gb/products/safety-security-emergency-communications/security-intruder-alarm-systems/secureconnect/build-a-system.html
also the new siemens (now vanderbilt) has most of what you want. There is also a an mqtt broker for that panel
There is a member on here that has an mqtt broker for the galaxy range using virtual rios etc.
Id avoid simplisafe its not a pro system, like yale etc. There are tonnes of vids on you tube on how to get around the security of these diy type panels