It might also be nice to have a fold current heading hotkey that is not quite toggle-able because it would move your cursor to the beginning of the line immediately after the heading before the one you folded.
Assuming you regularly find yourself in a completely unfolded heading hierarchy, which I would imagine is common, I see this hotkey going backwards as the direction of choice as it would allow you to quickly work your way up a hierarchy by repeatedly hitting this hotkey and then back down the heading hierarchy just by moving to the heading of choice using your scroll tactic of choice (arrows, wheel, page up/page down, etc.)
All my ramblings aside, I love the idea of being able to hotkey manipulate fold state of current zone, perhaps also for outline pane, lists, explorer, etc…
Thanks