I much like Quod Libet. It has a clean, functional interface to manage your local music collection. Also support for Plugins is nice.
You can create Boolean Logic filters like (played < 10 times AND genre = classical AND composer = Mozart) which I appreciate. And some of the included tools like being able to automatically create meta data tags from file names (for instance <artist> - <album> - <track>.mp3).
It’s the best replacement for Music Bee (Windows only) that I’ve come across.