Here is what I'm thinking about doing next, using a nice white-on-white I have. The color on the outside will be from the binding - otherwise the borders will just be the white-on-white. I'll quilt it with white thread. I'm thinking about calling it 'Hopscotch' since it reminds me of my nieces drawing hopscotch outlines in colorful chalk on their back porch.
A possible variation is white lines on a colored background (above).