A worryingly high number of ideas and posts are about getting functionality back. Design such as moving the play button is one thing but removing the ability to see all song from an artist from that artists page is totally different.
The search within playlists, the Podcasts..
Many of the highest voted for ideas are about bringing back or changing something.
when Spotify needs to do their major functionality redesigns they should have to do an open beta and a community vote before going live.