I use them the exact opposite.
I rarely blend. I like to lay in big bold blocks of color and the wonderful ability of pastel to paint layer over layer and build up like pointillism true color next to true color without the mud of liquid media. Your piece is simple and relies on local color.
Pastel is excellent for using complements under colors to enrich them. People think of it as a "soft", "light" and "delicate" medium. It is so much richer and immediate when used to its fullest range to portray color, it is a shame to waste it. Just posting one of mine to show you what I mean.
http://www.wetcanvas.com/Community/i...dydetailwc.jpg
Like I said, it is MY two cents. I am not right, just opinionated