Enchanted books are one of the game's more prized loot items, and are always exciting to discover- I for one always play with the visual enchantments resource pack, which alters how enchanted books and equipment books look based on what enchantments they contain. However exciting it can be to find the enchanted book you're looking for, it can take a really long time, and you can wind up finding a lot of books that aren't especially useful. (I'm looking at you, Bane of Arthropods.) It would be interesting if players had the late-game option to craft enchanted books using various materials, using existing resources, but for a considerable price. ...I included some ideas for recipes in the attachments.
-Enchanted books require fairly advanced materials to craft, and doing so only produces the first level of the book.
-Enchanted books of the same type can be combined to create a higher level enchanted book that combines their current levels. In this manner, combining two 'Mending I' enchanted books on an anvil creates a 'Mending II;' and combining the mending II with a Mending III creates a Mending V. If the result exceeds five, it creates a level V enchanted book.
-In a similar manner, an enchanted book can be split into more less powerful enchanted books. You could, for example, combine a Book of Protection V with four more book & quills to create five Books of Mending I.
-This would encourage players to collect and farm more obscure resources, and allow highly advanced players to enchant things without relying so heavily on villagers and desert temples.