We are just about completed with the Piggy-Back house second floor rehab. Here is a plan showing the before and after layout. As you can see, we reduced the size of the secondary bathroom to fit a 4th bedroom into the plan. We also made better use of a hallway connecting the master bathroom to the master bedroom by building custom desks and file and book storage. In the master bedroom, we raised the ceiling to match the small cathedral portion they already had so that the entire master bedroom has a peaked ceiling. In addition, we better utilized the shape of the room and created 2 large master closets behind the bed wall.
The big trick in all of this was figuring out how to tackle the house plan changes while keeping the original West exterior wall intact. This wall, which now separates the two bathrooms, is crucial to the structure as it carries much of the roof weight down to the foundation.