I can’t give you any ST specific advice, but I figure I can share my Hubitat to HA experience as there may be some tidbits that could be useful for you.

The biggest bit of advice I can give you is around the other people in your house and ensuring their experience is similar or better than what it was. I did this two ways: First, as mentioned in the other comment, link ST to HA and slowly transitions devices to native HA (I have z-wave and thread/zigbee radio). Second, I bought two low-end Android tablets, installed the native HA app, and created meaningful dashboards. The UI change alone between Hubitat and HA was a huge win. Not sure what ST’s UI is like, but Hubitat blows chunks.

A lot of your transition is going to come down to how the other people in your household interact with your smart devices. If you use Google or Alexa, then make sure to keep similar names of devices or groups as you move them over to HA. If you primarily use the mobile app, take the time to walk everyone else through the UI and make meaningful, mobile friendly dashboards. If you rely mostly on automations through sensors, make sure you set up the automations in HA as a part of transitioning devices.

Take your time, I rushed a few devices and got some constructive feedback from the wife about it. Little did she know I had already transferred 50% of the devices.

Learn the YAML configuration patterns and capabilities through templating for automations. The UI does an “OK-ish” job, but you can really unlock the power of HA if you take a bit to learn how to set up automations using templates and calling the back end services. Learning this took HA from “slightly better” to “way better” than Hubitat.

Enable Home Assistant Community Store, commonly referred to as HACS, to get access to a lot of open-source tools and add-ons for HA. Development is very active in the community for HA and there are a lot of fantastic integrations and UI upgrades.

I can’t stress the “take your time” part enough. It’s been tough for me because I get distracted easily and since this impacts the productivity of my family I wanted to make it the best for them. It’s been about 6 months since I’ve started the transition and I finally just powered down my Hubitat yesterday. The family is enjoying the automations and dashboards much better than anything Hubitat provided, but it definitely took easing them into it.

Hope you enjoy and feel free to let me know if you have questions - I’m still a beginner at it, but have really liked the platform so far.

I migrated from ST to HA this year and haven’t looked back, I got Home Assistant running and then took a big bang approach by unpairing everything from ST and then paired them to HA, I then wrote all my automations again, took a couple of days before everything was working again, I have 44 devices so didn’t take too long. I also had 2 ZWave devices otherwise everything would’ve worked off a single dongle which was annoying.

Best of luck with the migration!

I started by connecting ST to HA. It let me learn the interface and automations and slowly transition without breaking what I had, so that’s an option.

Beyond that, it’s mostly device specific as to whether something integrates easily in ST vs HA. Most issues I see are with cloud services that might have had an official integration with ST, but unofficial with HA and they break sometimes.

Speaking of breaking, HA development is much more active than ST so things are constantly changing. I try to keep up with the monthly blog post and pay attention to the breaking changes section before updating, so it’s much more hands-on than ST.

I’ve also personally moved many things from zwave to WiFi with ESPHome and Shelly. Wifi devices can have cons, but if your network is built with IoT in mind you can mitigate a lot that. I like that things are accessible over the network or even as a direct connection without needing the hub.

Overall, I’m much happier with HA and the experience has improved drastically in recent years. It’s a fun hobby.

Good luck!