I have a suggestion to improve the library. Sorry if this has been suggested before. I thought it would be a great idea to be able to search for new content by number of unknown words (or percentage of unknown words), and to be able to ignore content with 0 unknown words (or previously “I know all”'ed content". It would make it far easier to search for something appropriate to someone’s level.
I know you get lots of requests for updates, but if you could consider this, I think it would be greatly appreciated.