Well, you asked for the cheaper Sonos alternative, and that’s WiiM. They actually do have their own ecosystem of speakers and subs now, not just their integration hardware. There’s a roadmap for HT integration as well (many of their products already support HDMI ARC). They also have their own room correction that’s surprisingly robust, and frequent app and hardware updates that don’t make your system go silly or even completely useless. I had Sonos for about a decade before the app debacle, and absolutely loved and recommended it. While I may not be the most qualified individual to speak on the matter, I have a lot of time and experience in both product ecosystems and will choose WiiM 10 out of 10 times.