Scribbled Butterfly design would be great layered over other designs since it is just a simple outline. Stitches out in under 5 minutes.

You will receive 4 sizes in this pack: 1x1, 2x3, 3x4, 4x5
All designs are a heavy backstitch, as seen in photo 1, except for the smalles size 1x1 which is a single stitch, as seen on the purple backpack

Other designs seen here: Paint Splashes and Cheeseburger Font