When browsing the file explorer it would be good to get some kind of indicator (maybe a bubble with a number). It would be a good way of highlighting a file if you see a high number of occurrences (backlinks) from it to other documents (connectedness).
For example maybe I add a document called white Russian and in it I have vodka as a back link. I then see that there’s a bubble with a number 10 next to it because vodka also features in a lot of other recipes.
This would quickly answer questions like “what relationship does this document have to other documents”. It would be cool to pop it as highlighted nodes and paths in the graph view.