Music
Swinsian
Music collection, playlist and player. The UI looks a bit outdated though.
Petrichor
Music player. More modern UI, but lacks the ability to edit track info.
Elmedia Player
A music player with modern interface. I like its UI more than Swinsian, but I prefer the collection and playlist features of Swinsian.
PlexAmp
It’s like your own Spotify. You share your music on a server and access your music from other devices. You’ll need always-on device as a server though, so I don’t get the hype (??).
Video player
IINA: Media player
More handy settings than the default player.
Misc
Alcove
For adding little cool things to the notch.