I'd think since all the pieces already incorporate the seam allowance, it may not be needed to do the 1/4" seam (or less). I would first try the fusible interfacing and then a smaller zig/zag stitch and see how it goes.
I went to a quilt shop in MN where they had a scottie dog quilt called Bitsy and Friends and that is how they did it. Light fusible and small zigs. It was adorable!
Good luck and let us know how it goes!
