For books that you just want to read or want to get around to reading there should be a bookshelf feature.
The bookshelf should appear on the sidebar.
The bookshelf should be empty by default and users only add the books they really want to get around to reading or are reading now... I know they can be added to the short-cut bar but the icons are so tiny and every time I see an interesting book I didn't even know I had in the library preview I add it to the short-cut bar... it can easily get way to full ... it would be great to have a add to bookshelf option for every volume.
Doing this through a collection is not a great user journey.