You could use the lightweight or featherweight fusible interfacing. I think this is an awesome idea when working with lots of really small pieces of fabric. I have a pattern for a Mondo bag and it uses 2 1/2" squares but came with the printed interfacing to make the sewing of all those blocks easy. The lightweight or featherweight don't had very much stiffness. These are used in garment construction when just a little bit of stiffness is needed. I have lots of it as I used to sew mainly garments. I'm going to use it when I get around to making my postage stamp quilt.