Ok I played around and constructed a flash bounce very similar to yours as well and I would like to post my very unscientific and perhaps practical results in your thread.
Using the 360 FGZ:
Undiffused, ceiling bounce with deflector (but admittedly the ceiling was only 5 feet over head)
Using diffuser of the flash pointed right at subject
Using the do it yourself diffuser
Maybe I should have chosen a subject that sits a little more motionless but at least you can judge the shadows of the chair and the light reflection on the wall.
I am sure many of you have seen examples such as these before but I hope this helps someone.