Color choices

I've got all the pinwheel blocks for the one quilt.  Now I need to put sashing and cornerstones together with the blocks.  Here's a sample of some sashing material I'm considering using:

I'm thinking if I use this for sashing, I'll use some kind of white for the cornerstones.  There will be two borders.  The first border will be two inches and I'm thinking of making it blue.  The second border is going to be four inches and I'm not sure yet what color to use for it.  Maybe a green or pink.  Any suggestions?