Sure there are all sorts of edible flowers but have you actually eaten them? I have, they taste like, well, like flowers. Wouldn't you rather eat something that looked like a flower but tasted sweet? Of course you would.
I love a repeating pattern, especially on food. Even better when it's done with something as delicious and natural as blueberries. Nothing fussy, no artificial coloring or hours slaving over perfectly smooth icing, just a fantastic and undoubtedly delicious polka dotted tower of celebration. I'll toast to that!
Source: Poires au Chocolat http://www.poiresauchocolat.net/2010/04/blueberry-and-ginger-layer-cake.html
So much cupcake decorating is based on the notion of piling heaps of stuff on top of the cake, it's refreshing to see someone make use of negative space here, so to speak. A creamy pool of frosting in the middle of the cake is a nice change!