Over the past couple of years, I've used Literal to keep track of the books I've read and that I’m reading. When you mark a book as completed, …
On rating books
Manuel describes exactly the behavior that I have already recognized in myself:
I suck at this. I genuinely don’t know how to rate things on a scale, which is why the vast majority of the books I rate are either 4 or 4.5.
Almost all of my books are rated four stars, sometimes three. Since five stars automatically make a book a favorite, that rarely happens. So I think the idea of a simplified rating system is a good one, and I might try it sometime.