Thank you for this new layout, this is something I was looking for.
I use Calibre for my own scanned books and always wanted to have it looks like my current shelves.
I have a request for this new layout:
Could an image be provided as the side cover to override cover squish. I have scanned my book spines (or sides), and it would be great to use those. The page image for the side is always the same height as the image book cover, so width could be used for ratio of display. This should avoid distortion for resize to display on shelf. Override could only be a checkbox and check if a file spine.jpg is in the book folder, in that case only use the image resize, otherwise use the current automatic generation with title and font.