I fully agree with this approach! 5 years ago I built a prototype to execute that same concept of language covering. But instead of just using words, I used n-grams. It ii trained on subtitles to model spoken language. Combined with sqlite in the browser to get the next sentence with the most impact.

github here: https://github.com/fdietze/ravioli

prototype deployed here: https://raviolio.web.app/