Carol -
The Kaufman fabrics that Amber suggested look like they will fit your vision for this beautiful quilt. I also like the fan corners that you incorporated based on Sewcrafty's suggestion. You've done a great job laying this design out; I hope you enjoy the process and the finished product. I'm looking forward to pictures of your progress.
On another note, your design could easily be adapted to a 2-, 3-, or rainbow-colored project. I have too much on my plate to attempt it right now, but I would be curious to see another interpretation of your pattern. Do you plan to post or sell your design?
Darren