The rel module (renderable elements) makes it possible to have *all* the elements available in your manage fields screen. That way you can (for example) break out the vertical tabs into whatever you like, remove all the field groups in it, and put one thing in the main column and the other in the right.
This works for 90%.
The problem is some fields which become available through rel are not available in the manage forms screen. In my tests these fields are unavailable:
- comments (comments open or closed)
- url alias
- menu link fields
All others are available (authored by, revisions, date, promoted&sticky etc) and respond to region changes.