The Center for Health Research and Transformation (CHRT) has a chart that is making the rounds showing how people will get health insurance in 2014 if the ACA is implemented :
I have been showing it to people and asking for their initial impression. Most initially say that it is complex. Upon closer inspection, some say it is actually two charts: a very simple one for persons who are age 65 and older, and a more complicated one for everyone else. If simplicity is your goal, we could easily have a system that could be represented as a one-box chart.