Have you ever tried facing a quilt? Do the SITD as you planned, then do the border. Use leftover jelly rolls and place them right side down on the front of the quilt. Sew around, then turn the facing to the back. That way it will be wide enough to cover any shift in quilting. You wouldn't have a border showing on the front, but IMHO the quilt is gorgeous as it is and no border is needed.