1st if you go with HA/Home Assistant, be prepared to spend a lot of time coding yaml files to get the setup you want. I have a love/hate relationship with it lol. It's definitely not a plug & play type of system. From my understanding, Smartthings (I don't use it), is much more user friendly for the average consumer. My HA system is an experimental system. I expect to retire in 5 years & want my next house to be as automated as possible. So, this is my learning system. Before I started, I had a couple smart iot (internet of things) connected to my Google Home & quickly saw where the number of apps could get out of control (sounds like your wife lol). I'm running HA on a little Raspberry Pi 4 (RP4). I have about 15 devices (mostly lights/switches) hooked up & it's running fine but, I don't use any cameras. I've heard cameras can make the RP4 struggle & don't even think of adding any facial recognition software on a RP4. If this wasn't my experimental system, I would definitely be running HA on a more capable computer/server. The advantage I see of HA over Smartthings though is avoiding the "cloud" & keeping your data & iot communications local (or as local as possible). If the internet goes down, the devices that communicate locally will still work. I've currently got HA working with GE/Jasco, Levitron, Inovelli (I love their switches), Bond Home (ceiling fan/light) devices as well as my Google Home & Harmony Hub (entertainment system universal remote). I am trying to keep as many as possible iot devices off my WiFi & on their own communications protocol. So I have a lot of Z-Wave devices & like them a lot. I haven't tried Zigbee devices yet or Lutron.
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