Build from product truth
Start with the primary SKU and its approved media. Define what must never change: color, construction, logo placement, proportions, and included accessories.
Then define composition separately: background, camera height, shadow, crop, and room for marketplace overlays. Save these directions in the project or a private Skill when they repeat.
Generate alternatives as children of the same source. This makes selection and cost review much clearer than overwriting a single image.