Matthias that concept of a shared whiteboard focused on Scripture is exactly what we’re prototyping! 
We’re starting with Miro, which we’re sort of discussing in this thread. Miro has been the closest tool to the experience of whiteboarding that I’ve found so far.
We put some Scripture on it and it’s easy for multiple people to read together, put down stickies, and see the presence of other participants’ via their cursors:
You can also easily zoom in and out which we were using as a way to give a sense of “space” in Scripture. When you zoom out you can see the “shape” of the Bible:
I found it quite insightful to be able to see old and new testament like this and the lengths of books, where they are in the canon and connections between texts and then to be able to seamlessly zoom in for details on things that interest me.