I made a PR (= pull request) with some additions to the db schema; it would be useful if you provided some comments.
Also, I was wondering: would it be useful if I wrote, purely as a skeleton starting point, a few classes that provide data interfaces for reading/writing blocks, revisions, pages? I have some ideas on how to do that from previous implementations, and I could write them as starting points that we could then build on. Sometimes having something concrete as starting point is helpful.
In fact, I could even do this more in general, and write stubs for classes for various tasks, just to offer some trace for the implementation; would you like me to do that? It might help getting things started... it's often easier to start by modifying something than by contributing from scratch...
Luca