Wuk,
I think you have definitely hit on the idea for the chart. I really like
#28, it has good colors, the axis, and everything else I think it needs. I really like the concept, and I can't think of anything else that would improve it.
Thanks for experimenting with other variations, too.
#27 convinced me that the two color scheme is better,
#26 convinced me that no tic marks are better than tic marks, and
#29 convinced me that my thoughts about making some of the words out of focus doesn't work too well (there are so many bad graphics on the Web, that I don't think you can always tell intentional un-focusing).
I'm going to put some of these variations lower in the rankings just to declutter, but know that I do it only because your best variation stands out at the moment.
Thanks again,
Phil