Pretty cool, interested to see where you take this. Have you checked out Hypothesis? It's a similar tool thats been around for a long time: https://web.hypothes.is/
Thanks. Ya, I actually spoke with the founder of Hypothesis a while back, and a former contributor who was looking into using Kontxt. Kontxt not only enables rich web collaboration, but it helps atomize the web to re-use key pieces in secondary contexts like a social network or in the future, to create new content. Kontxt takes a social first approach with many ways to share and follow with others.