This isn’t the cheapest option but I use the keypad on my Schlage Camelot lock to disarm the alarm using Lock Code Manager. Just something to consider if you plan on installing smart locks.
Some users do not use SHM because it does not have any delay actions. Smart Alarm will allow you to set delays for ingress and/or egress. The downside to this is you lose the dashboard that SHM offers.
There may be a custom device type for the Aeon Labs siren that may allow you to disable the light. I don’t have one so I can’t say for sure.
Depending on how new you are this link may be useful. Check out the FAQ section. It has instructions on installing smartapps and custom device types.
http://thingsthataresmart.wiki/index.php?title=ThingsThatAreSmart_Wiki
Once you get comfortable with the platform you may want to check out Rule Machine. It allows you to do a lot of things you aren’t able to do without writing a custom app. It could be a little overwhelming for a newbie depending on your technical level. Make sure to read the release notes at the top of the thread.