There is a bug right now that doesn't follow your "omit from shuffle" setting on iTunes. And, you now can't shuffle an artist without having to click on the icon (not the text), and then hitting the shuffle button there.
Little things of course, but you know... I use those things!
It only shows you 20 of your "Up Next" songs too. It has to "redraw" when you rearrange stuff aswell.
Nice changes overall though. I am enjoying the custom images for playlists in particular. You can set one for folders, and even the Genius playlists (I have mine set to the song's album cover instead of the collage of what's inside the list). So while it's overwhelming, it's a lot more special. Would have loved that in iBooks though.
Have no interest in Apple Music either. I've tried all these services, and I either don't find myself using them, or I end up stuck in a few albums/playlists.