The area measurement is almost perfect but one thing that would make it really handy for what I do is add a length measurement for each line and then a total perimeter. I do insurance inspections for a variety of companies and they want the length of each wall and a total building perimeter. If you could make something that shows that data that would be perfect.
Maybe you can do a tool like the volume measurement where you draw a box around a building and it will create a little diagram showing the length of the walls and the total perimeter. Throwing the square footage into that could be useful as well.