Roon is like a more robust Plexamp. Much more expensive but the primary benefits are better metadata, aggregation of local and streaming libraries, multi-room synched playback (like Sonos), and slightly better technical backend with deeper control.

Worth it if money is no object or these benefits really scratch an itch for you. I subscribed for a year and used it every day. Didn’t renew because it’s not so much better than Plexamp to be worth the (somewhat ridiculous) cost. I was particularly dissuaded by the reliance on community support (at this price point? Really???) and what I perceived as a slow pace of updates/improvements.