I don't care if Pitbull paid to promote his music on Spotify. The reason I paid for Spotify is to stop seeing such advertisements. I would happily pay even more just to stop seeing these things.
Please reduce the amount of resources needed by Spotify to start up.
I have to wait several minutes for Spotify to start on a laptop with 20G of memory and 8 threads at 3.0Ghz. Excluding users with older hardware reduces the number of users and reduces your sales. Adding features that use more resources is bad. Even worse, if a feature is not used, it is wasting energy, slowing down the user interface, and annoying your users. Removing unused features and reducing the amount of used resources will make your users happier. No one likes a laggy interface.
Please add an option to disable notifications (the number in the red circle).
Go ahead and make a list of notifications somewhere in the background, so I can view that list at my leisure. Do not notify me about the list if I don't want to see the notifications.