I really like the minimalistic full-screen mode with just the album covers for purely enjoying music. I just missed one simple feature so far, which I know and love from YouTube: I want to quickly switch into full-screen mode, to have a comfortable view to my friends and me. Just pressing a keyboard shortcut would be great.
It looks like your idea was posted a while ago but, unfortunately, it hasn't gathered the minimum amount of votes to stay active in the Ideas Exchange (50 votes in the first 3 months). I'll mark your idea as "Closed - Not Enough Votes". You can learn more on how the Ideas Exchange works here.