If you have a large collection, one of the best ways to bring harmony to your shelves is by sorting your books by the color of their spine. This won't work for everyone, BUT if you're an especially visually person, like I am, it's easy to associate the color spine with the book you're looking for, so you can find it quickly.
Once the spine colors are separated, you can style each individual shelf with a different color.
What you highlight on the top shelves really depends on the colors in your space.
If your space is more neutral, start with the whites and blacks on the top and leave the color for the bottom shelves.
As other option, if you have a lot of red in your rug, try doing warm to cool incorporating your whites up top with the warm tones and blacks on the bottom with the cool.