One way to give oomph to a set of fabrics is to pick one "zing" fabric. A zinger can be a fabric with a really different value than most of the others. Darker or lighter. Or it can be more saturated than the other fabrics. Or it can be a complementary color to the main fabric. You don't need to use a lot of a zinger, a little goes a long way but it does liven things up.