What great contrast in your mini! I'm not a big PP, but do like to make mini's. As to color selection, I have found you need to have a contrast between fabrics next to each other if you are going to see the patchwork design. Also when using fabric pieces that small the smaller the design in the fabric the more attractive the block. You can use larger designs, but the overall look changes. Often times mini work is a lesson in value (light and dark) placement.
On a another note--when quilting I think less is better as the star of the quilt is the minute piecing, not the quilting motifs. Looking forward to seeing more of your work.