That is a beautiful quilt, can't wait to see it finished. I think the dark color in the center would be good for the sashing, a 1st narrow border and the binding. Maybe a batik with all the colors for the border?

PS: Or how about your background fabric with some of the PP elements incorporated (maybe 1/2 of the pattern?) Can you see what I am thinking?

I would sash with the red, then a small border of the cream to frame it, then a wider border in the background color of gray/black.

me i would skip sashing and go to the borders, do a yellow or red 1-3" then a wider 5" or so of the background fabric. then bind in red or yellow which ever you don't use in the border.

I would use your darkest color for sashing (black? navy blue?) and a narrow double border of red and the same dark color. It has enough yellow. Very attractive blocks.

That's my suggestion, too. I think I'd go with the red. Then your background fabric. This is a real stunner!

thanks for all your help