I agree there, Kass, it looks like of muted. I am having a hard time seeing what the pieced sashing brings to the table. Maybe just solid coral, or aqua, sashing would help it.
Edited to add: Maybe the pieced sashing is supposed to look like ribbons circling the blocks? I can kind of see that. Ummmm, what would they look like in blue then? As you can see, I'm not ready to put this one together!