I'm a fan of compatibility with established formats!

Sounds awesome. There is a lot of untapped potential with respect to efficiently archiving and indexing websites. I saw the impressive things Marginalia Search is doing in this area (the blog is great when it gets technical). There is also a lot of very complete archives of websites out there which are not being indexed at all, and I would love to make them available for researchers. In any case, I'm interested in your project!