Often times, I have this driving need to fill the entire canvas with design work. It seems more balanced and like there was more time spent on the actual design that way. In reality, this is often not true.
Sometimes, by leaving most of the area very simple and only have a small area of complex design work, this accentuates the complexity and brings out the subtleties of the design overall.
With this design, I have a very intricate and complex set of swirling designs at the center and only very faint hints of pattern around it.