You can also cut leftover lightweight fusible into strips and use it instead of the tape.
I'm very impressed with how organized you are. I save my batting pieces also, larger pieces in one place and smaller bits in another, but I never seem to do anything with the smaller bits. I make mostly large quilts, and buy 90" W&N on the bolt, so almost always have to add something to get to the size I need. I wish JoAnn's sold wider W&N on the bolt!