Another type of book I really like is the "Silent Book" or "Book Without Text" (I don't know the correct term in English).
Being able to tell a story without writing anything is brilliant. These books can allow the reader of the image to create their own narratives. The author provides a path or poses some kind of question with the images, and it's up to the reader to create their own understanding.
Obviously, this type of book isn't just created by illustrators; text authors can create a script and guide the illustrators to do what the author envisions, and together they create a great book.
And best of all, it's universally readable; no translations are needed.