I like the iTunes 12.4 update

The top navigation bar has had several buttons removed, and the app uses a persistent sidebar instead of multiple drop-down menus to let you view your media. iTunes versions of yore also made heavier use of sidebars for navigation—sometimes the old ways really are best. Finally, the back and forward buttons now let you "navigate between your Library, Apple Music, iTunes Store, and more."
What does everyone else think?

It messed up my mind for awhile until I figured out where everything was located. The only thing I use iTunes for is to sync our iPhones and to import our home recordings that we make. We then fill iPod Shuffles with the home recordings. The new iTunes is not really a big change.

One extra thing you can do to reduce clutter and make for a nice menu bar at the top — assuming you don't use these options — go into Preferences > Restrictions and check the "Apple Music" and/or "Connect" boxes. This removes them from the options bar at the top. Naturally this only applies if you don't use either one of these.

Ian