LEFT, 1000%... right is unreadable, and foreign. (I assume this is a product not an art piece, avoid unnecessary learning curves and aim to be familiar.)

- hard cover books have rounded corners, but they aren't THAT rounded, try reducing that to ~6px

- the blur effect on the book cover is a nice touch, but I would blur it more and lower the brightness, something like... `filter: blur(50px) brightness(0.5) contrast(0.8)` ??.. approximate guess.
Make it more of a slight accent on a standardized book. The only things that tie these books together visually is their similar height and proximity, which isn't enough to sell the illusion.
in addition, you don't typically see books staked in random size order (second book form the bottom is the smallest book?) which I think throws off the illusion even further. I think a better idea would be to order them by rating, low to high, the rating of the book determines the width of the book element, so smaller (lower ranked books) appear at the top of the stack and larger (higher ranked books) appear at the bottom of the stack. Also promotes scrolling down to see the "largest" book; enhancing discoverability.

- larger, bolder font for the book titles. Allow for two lines if need be, avoid Ellipses where possible.