I always thought the prefolded diapers were too thick down the center. Instead, I made some using flannel on one side, and terry cloth on the other. They were colorful, soft, and absorbent. Be sure to prewash and dry in hot dryer before making - the two fabrics shrink at different rates.
You can embellish with colored ribbon, fancy stitches on your machine, or even appliqué.
Good luck, show us some pictures of your finished product.