He designed a cut-out place where my foot pedal can fit right into. (see second photo) It is wonderfully sturdy, but not too heavy. I think it will look very cute when I paint it with something whimsical, and I also think I'll ask MisterStitches to add a simple handle onto the side, so that I can carry it to another location easily.
This shows the cut-out portion. Isn't my son clever!?!