It is important to keep all of the fabrics used in a quilt about the same quality. If fabrics are significantly different in quality they will behave differently (shrinkage) and distort the elements of the quilt. Also, the wear pattern can be a problem. Adding fusible interfacing to some blades in the pattern will add to possible problems. My suggestion would be to add interfacing to all of the blades so they all behave as a unit.