I love a good home library. It shows, too. Our moderate-sized apartment is packed to the rafters with bookcases, so full that we have to have bookcases behind our couch (and there's no room left for walking between them, so the bottom shelves are, unfortunately, covered). I look forward to getting a house for many reasons, but not far from the top is to have a library or at least more wall space to press bookcases up against.
My bookcases are filled, for the majority, with romance novels and fantasy, with a shelf or two of nonfiction, cookbooks, and Cody's thrillers. Which means that my walls are a collage of color and size, ranging from pastels of romance novels to the eye-popping colors of thrillers (and Evanovich novels) to the black of fantasy novels. Looking at all this color is incredibly pleasing to me. I can pick out a specific title from across the room just by the color and size of the spine.