I would sash so that the swirly fabrics don't run into each other. Depending on what you're planning to use the quilt for, that would decide the color of the sashing. For a baby quilt I would use a light color and for an adult lap quilt I would use a dark color.
Thanks for posting this - I just got a bunch of clearance jelly rolls at Tuesday Morning too and had been wondering what to do with them. I like your choice of blocks.