My off-topic rant: I'd really wish Spotify would focus on improving the core player experience. It has barely seen any improvements in years.
* Not overwrite/delete my listening history everytime I switch devices
* Allow tabs, or some way to resume what I've been listening to in different contexts
* Option to open only one instance, instead of having multiple instances that mess with each other
* Playing local files crashes/not working on Linux
* Change playback speed, not just for podcasts
* Jump back/forward, not just for podcasts
* Have some visibility when the song was last played / play count
* Liked songs not always appearing in search results
* Sorting search results not working
* Add basic functionality to the dbus interface (e.g. seeking)
* Ability to report songs (e.g. wrong titles/badly split tracks/etc.)