For #8 and similar concepts, I like the tiles. The mosaic effect is definitely appealing. Could we do a progression of color and smaller tiles? Here is an example of what I mean (though it's not a good example necessarily because it looks like there is some kind of abstract face in it):
http://th01.deviantart.net/fs47/PRE/f/2009/170/2/0/Vivid_Tessellation_by_ARNDAY.jpg