If you are using a bookcase with multiple shelves here are a few ideas for that. If the shelves are deep you can use them as as a sort of backdrop allowing you to have a display area in front of the books for memorabilia, small knick-knacs or even framed stand up pictures. Hardcover books are best for this. Each shelf can be a little different creating different aesthetic "stages" if you will. You can have a row of books of the same height and width for a uniform look on one shelf. The next shelf could have taller and wider books on both sides of the shelf going with progressively narrower (and shorter)volumes as you head toward the center of the shelf for a curved look. You could also start from the left with the smallest book first with progressively taller and larger books going to the right. Written english is read from left to right which makes smaller left to taller right more aesthetically pleasing to the eye. If you don't have a lot of hardcover books you could make half of the shelf for books with a flat metal bookend on the center side so they don't topple and devote the other half of the shelf to larger statuettes (with some sort of theme)or picture frames. the next shelf would be reversed possibly with another theme. If what you are using is a wall mounted shelves, I would still move them back toward the wall. This will put less stress on whatever is holding it to the wall. If you have a hodge podge of sizes it is best to group them by similar sizing again shorter left to taller right. Dusting is required for the above ideas. A couple of my book cases,which have deep shelves, have the hardcover books pulled toward the front of the shelf with a row of my paperbacks behind them (I am a voracious reader with a whole lot of books). I don't have to dust those shelves as much. Multiple shelves traditionally will have shorter books on higher shelves and taller books on lower shelves. Wow I didn't think I had much to offer you but looking at what I wrote, I guess I did. I'd better stop before I rearrange your entire house.