Thanks for the explanation.
Could that "one" button in the toolbar also be a dropdown box, just like it currently is also used for filtering for tags? That way, the complete functionality could be put into that one single button:
- just click at it (in the content area): show HTML temporarily;
- clicking at the small "v" would expand the list, showing the three available view modes;
- picking one of these sets the current default view (the same way as previously in the status bar).