So what if (? ) you are following a pattern and the pattern has 2 colors. what if (? ) you create variation within each color to make it more interesting? I have used this method before but I thought I would detail its reasoning.
I picked a nine patch. because of its simplicity. And black and white for the same reason.
5 black squares and 4 white squares. But all the blacks are different. And so are the whites. Still reads as a nine patch but more interesting, don't you think? I think so. Plus, a great way to use up small scraps and not buy more matching fabric.
Tip...I also varied the types of fabrics in each color category. This makes the color and the texture variation add to the visual depth.
When substituting colors you can break the rules, a pale color can also be used as "white" against black. Likewise a very deep shade of another color can be used as a "black" against white. It's like magic.
I have applied this idea here, as I begin a new cloth.
I use this method to hand piece most of the time: