It's been a rough few weeks but I finally got back to this. The code currently checks each unique word usage against the Fry list. I have the Fry list words sorted by grade level but the first push was just to integrate the list into the book reporting.
Code:
Fry Word Usage:
Used 800
Custom 0
Miss 3629
The plan is to allow a user to set up a custom word list so that the "Miss" rate can go down and the Fry ratio improve. I'm also using my idea of "custom word list" as "stuff I should write a library data entry on".