I recently tried several music players after some comparison and I ended up
chosing Sayonara Player wich seems a good choice for organizing and listening
a music collection
https://sayonara-player.com/
I searched something light that would let me do that simple tasks
efficiently, without tons of features I never use.
It is free software GPLv3.
It associates a good looking interface with advanced files tagging
functionality and cd covers search and download. Like Clementine, it has a
smooth volume transitions between files, wich is a must have for me. It also
features some web radios, including soma.fm that I like. I tend to use it
with kid3 to tag a large number of files.
Guayadeque is also a good choice regarding files tagging and cd covers
handling as it is able to and write the cover image on files metadata for
multiple files at once. Some sites claim Sayonara can also do it, but as far
as I understand it just pastes the cover on the album directory.
I also like installing the Python script Cd cover thumbnailer
https://projects.flogisoft.com/cover-thumbnailer/ (requires nautilus for
installation but works well with Mate after that), though it uses some extra
ressources for displaying the covers.