For reference, this is what the different star ratings mean to me:
1/5 stars: I pretty much hated this book.
2/5 stars: It was okay, I guess, but I can’t say I liked it.
3/5 stars: I liked it, but I had some issues.
4/5 stars: I liked it a lot, and only had very minor issues with it.
5/5 stars: I loved it! No problems whatsoever, or else any issues I had were overwhelmed by sheer awesomeness!
5/5 stars + sun: An all-time favourite.