'Rainbow' Lockdown List Quilt

I have made a quilt from the Document wallets that contained my lists from the Lockdown period. I stitched each seam with a colour of the rainbow in reference to the drawings in the windows. (I just want to hint at this).

The idea is sound, I think, but the outcome isn't quite what I had hoped. I think it may be worth removing the holey side and just having plastic pouches. Usually I just use whatever thread is on the bobbin unless I am making something very special but I don't think having the wrong colour helped, it diffuses the rainbows. Also the zig-zag could be tighter. Possible changes to be made! But the idea is there.