It would be nice to be able to select multiple notes in the sidebar and have them display the note content in sequence. (This is like the behavior in Scrivener or Ulysses.) It would make writing longer form stuff with multiple sections easier to do.
Just displaying the notes one after the other (with some knowledge of which note is active, to make the various info panes work).
Right now, the longform plugin provides some support for this kind of use case, but not precisely, and with a bunch of overhead project management stuff.