Yes - just a starting point. My focus was just on mode transitions. I am considering creating other diagrams that focus on other aspects of vim such as operators/motions. I may also create some simplified versions too. (But I am not sure I will try to combine everything into a single diagram...)

I admit this one is daunting at first. Keep in mind that it's just an early draft. As I was making notes for myself, it was fun to see it take shape... and it was kind of like solving a sudoku puzzle to get it laid out without overlapping edges. (The fact that it is planar is just a fun coincidence). I have other interesting diagrams that I have scratched out too...

Most of the modes and transitions won't be of interest to everyone. Think of it a roadmap/atlas of places you could go. (Some people may like reading tables... I like to see things laid out visually. Although I am thinking of creating an adjacency matrix that is partitioned/clustered so it can be collapsed into simpler views.) Just like people make simpler maps to tell friends how to get places, I fully expect it will be useful to make simplified illustrate that only shows a subset of this more detailed transition map.

Thanks again for the feedback!