I purchased Swinsian a week ago and I'm really liking it. I get the Column Browser back which the Music App took away, I no longer have to convert FLAC files to an iTunes readable format (a big time saver for me), and it's much zippier...iTunes (and the Music App) always had a 2 or 3 second lag when switching songs which never bothered me, but I think after using Swinsian that lag would bug me if I had to switch back to the Music App.
It's not perfect. There's no Dark Mode. And while Swinsian did import all my playlists, album art and star ratings, it didn't import my lyrics. Even if it did, the lyrics window is way too small and can't be resized. Also, editing track info is awkward compared to iTunes...you have to select a track, mouse to the edit window and edit your info, mouse back to track listing and select the next track, then mouse back to the edit window - there should be a "next" button like in iTunes.
Despite these small issues (and a few others), for me Swinsian is a step up from iTunes and/or the Music App and was well worth the $25.