The Echo Mini is pretty good and they’ve been updating the firmware to add stuff for a while now. My biggest gripes with it would be there is a hard limit of a little over 8000 songs even if there is enough space for more on your SD card. It’s something to do with how it indexes the library. It also doesn’t really support playlists, although I think the most recent update allows you to play everything within a genre so you could do some shenanigans with that.

If you’re on a Mac, I think ipods are still recognized and you can use their software to sync and manage music. You can only sync over music you own so no apple music obviously.