With HomeAssistant, as I understand it, it needs the full Pi? I have a bunch of services running on my RPi 4 and so when I’ve looked at HomeAssistant I haven’t been able to install this without touching the other stuff on there. I think they have a docker container version but it has a lot less features.
I'm running it dockerized as well as I'm using it for other stuff as well, like PiHole, media server, etc. No problems at all.
Some features are missing, like editing config files in the browser. Major gap is that add-ons are not supported. Add-ons are essentially 3rd party apps, like DuckDNS, Frigate or MQTT. It's mostly annoying because the documentation assumes you run the HASS version. But it's no big deal, you can set up those apps yourself. I'm running Frigate and MQTT dockerized and connected to HA without issues.
For docker resources, check out https://www.linuxserver.io/. I used to install apps like NZBGet, Radarr, etc. all directly, which was very annoying as each app uses a different install script. With the docker compose files from linuxserver it was a breeze. I only run PiHole directly, as I saw some issues with the Docker version, the rest is all dockerized.