Which crayon style feels right?

Strong pigment body with sparse clusters. Wheels are pre-rendered sprites, so their texture rotates without flicker.

Drier strokes with gaps where paper fibers show through. These can be replaced with scanned brush masks.

Fractally distorted silhouette, fully transparent pigment gaps, and a narrow intermittent core that keeps the shape readable.

The original dense, evenly granular pigment, now attached to the wheels and ball so it follows their movement.