>>12693 (OP)
i have a couple of bookcases to contain the books i read, and i can't say there is a very rigorous order. some are organized by size, to save space, some other shelves are ordered thematically.
the ones i hadn't read yet, the vast majority are divided in other bookcases or various pieces of furniture.
i find it both fun and unnerving browsing them trying to decide what to read next.