So after a first quick look, I have to say: very well done! Thanks!
I noted a lot of changes seem to be just spaces and punctuation (e.g. a dot changed into a comma).
Would it be a lot of work to rerun the diff checker while excluding these (almost certainly) meaningless changes?
It would be much easier to find the really interesting changes.
Also, would you be willing to share the wtlib contents you harvested? A lot of interesting analysis could be done on them :-D
PM me if your public response is no ;-)