The only thing I use, or used, the vim mode for was to move around a note by sentences, and to be able to delete half-written sentence that had gone wrong with a single keystroke. Especially this last function is incredibly important to me and perhaps to other writer types. So I have written a plugin to do exactly that. It works, but it needs prettying up before I offer it as an official plugin. I will do that if there is any wider interest.