[Rendar]

Things that could work for weapon customizations for it..

Bookmarks
Glue Type (???)
Ink Type
Book Binding
Thread Type.

Things like this would make them a decent choice to do. Well.... anything with them involving basic attacks. I've an entire list of this sort of thing from my sunday game where I got to craft my own tomes (which was hellacious btw)

Here's the stuff that we used for that, incase you want to have reference or get ideas from it.

https://ada-young.appspot.com/pastebin/30a42241