I found Hass.io (
https://www.home-assistant.io/getting-started/) relatively easy to install. The trickiest part was that my first SD card was corrupt and setting up the port forwarding and DuckDNS / Let's Encrypt (the latter because the port forwarding was wonky).
After that it has been a lot of experimentation and tinkering but nothing too complicated. I have Yeelights and Xiaomi sensors and gateways which was also picked up quite easily (although I had to configure some things manually). The YAML language takes a wee bit of time to get used to.
You don't have to use a Raspberry Pi but I only had an old Windows server laying around and didn't want to struggle with Python and Home Assistant on it (most of the guides are for Linux installations or Hass.io or a Docker image). I previously tried OpenHab on Windows and it was a struggle all the way. The Pi route was a million times easier.
Next up over the weekend is setting up the Google Assistant component and then flashing my Sonoffs with either
https://github.com/arendst/Sonoff-Tasmota or
https://github.com/xoseperez/espurna/wiki/HomeAssistant. Either you flash them via a USB UART connection or if your Sonoff is running the correct firmware you can use SonOTA (
https://github.com/mirko/SonOTA).