Sorry if you saw this on Reddit already, but I wanted to post my concept design for Xbox Music on Windows Phone here as well.
I decided to take a few minutes and make a quick concept design for Xbox Music on Windows Phone. I did this pretty quick, so it is not perfect.
I figured since we are all quite disappointed by the state of the current app, it wouldn't hurt to discuss some changes. I know many of the complaints are not design-related, but there are still plenty of improvements that could be made in this area. I think the overall design of the app is pretty good, so I kept it very similar with a few tweaks. I have re-designed the now playing screen and the playlist.
Total list of changes made to current state of Xbox Music:
Xbox Music and now playing headlines are much smaller
Moved the currently playing track to the top
Added album name
Made the album art much larger
Added a slider to the track position (similar to how it looks on the Windows 8 Xbox Music app)
User's accent color would be used for the slider and for activated shuffle/repeat as well as the currently playing track in the playlist view
Increased the size of the track controls and added shuffle/repeat to the right of them rather than to the right of the album art.
Re-designed the playlist and changed how it's accessed from Now Playing. In my design, you would be able to scroll this up to see the entire upcoming playlist, instead of tapping the current playlist icon. As you scrolled the playlist up, the picture background of the now playing would fade to black. Initially, the next song up would display at the top, but you would be able to scroll back to current and previous tracks like shown in my mock-up.
One of the biggest requests was the ability to swipe to change tracks like it used to be on Windows Phone. I believe this would work with my design depending where you swipe from, but I'd like it to be an option as people might try to pan over to the collection section and change the song by accident.
Its nice to see that also other people dont like the current Xbox Music app for Windows Phone 8.1 and therefore create concept designs.
You did a good job with your concept. I like that you made the headlines much smaller and that you improved the now playing section. Moreover the reintegration of the ability to swipe to change tracks like it used to be on Windows Phone 8 in the Music + Videos Hub is a huge improvement.
I also did a redesign of the Xbox Music app for Windows Phone. My redesign was focused on the creation of a universal Windows app: Thus I merged the current UI of the Windows Xbox Music app with the UI of the Windows Phone Music + Videos Hub.
Very nice work, although I'd prefer a smaller album image -maybe about 2/3s of yours, or even smaller. This actually it looks a lot like the playing screen on my WP 7.5 phone.
Edit: My comment was meant for the OP.