Over the years the "in" colors change so it is hard to match fabric from different decades or even from year to year. I find it is easier to use stash fabric with a neutral solid color or tone on tone. Even when a color comes back "in style" it usually has a different value and tone so it is the same but not the same(if that makes sense). I like the idea of scrappy as others have suggested, it is easier to add different values and tones than a planned quilt that needs to blend very well.