Hi Spotify,

We'd love to tell you about a use-case that's out there.

We've been avid Spotify premium users for a multitude of years and love everything about the product and the augmentation of the music industry you have been driving all this time.

Me personally -as retired Stage Manager- additionally believe that your soft (R)evolution has brought the artist back closer to her audience. And I'd love to thank you for that.
Alas, if you were expecting an obligatory "but" at this stage of the letter, we have to disappoint. There really is none. No remarks on how the cake is shared amongst the pool of artists, no lobbying for the music industry.

A lot of my music loving friends and myself would love to spend more on your service. As a Spotify PRO consumer. An extra €5,00 per month for instance.
With this PRO budget you could direct even more attention to discovery ànd build a new cake to share amongst the musicians we prosumers tend to listen to - less mainstream but high value. Think about it, you'd be giving us (the prosumers) an enhanced feeling of impact and customer loyalty, and you'd be helping out the emerging spectrum of the music scene.  

It is a win-win really.