I bought a huge cone of variegated thread (very expensive) and didn't like it for the reasons stated above. The different shades were too far apart. So I have been using it for piecing and on bobbins.
Now I am going to use the suggestions on this board and use it for decorative stitching where the thread sort of piles up more. A buttonhole stitch around an applique might be a good place for it. ? ? ? ?