It's called 'Circle of Nine' by Janet Houts and Jean Ann Wright. They give instructions for 24 quilts, which all have the same idea, of nine feature blocks arranged in a circle and the spaces filled in by rectangles of fabric, flying geese, four-patches or whatever compliments the blocks. This seemed to me to be ideal for my purpose. The only snag was that I have twelve blocks, not nine, but I decided to use three either on the back or for another purpose, so that problem was easily solved!
I think the baskets are busy enough not to warrant fancy spacers, so I chose this arrangement, with rectangles of fabric between the blocks.
And here is the fabric I have bought today. It's busy enough to hold its own with the baskets, but not in a position to overwhelm them. Now to the cutting!