@jbuhl - great point and list!
You asked what other features you might be missing so, I don’t believe I saw anything about how your system can continue playing the genre of music you were just listening to, after your specific selections have finished playing, i.e., Roon Radio. Sometimes I set up a dozen selections for the sole purpose of hearing what Roon Radio will add after my selections are done playing. I have been introduced to a lot of new music through Roon Radio and through the lists of "Recommended Albums", "Similar Albums", and "Similar Artists" that accompany every selection.
I will be interested to read if folks here identify other players that provide as much added value.