First of all it is a wonderful quilt.
I would inventory the fabrics left over to see how much is available. The question is: How wide a border can you get of this or that fabric. Keeping in mind that the farther out toward the outside edge you go, the more fabric you will need.
I understand you have an unlimited supply of black. So the picture with the larger black borders and accent 3/4 to 1 inch framing border is just perfect.