For brand illustration libraries: Leonardo AI is better for consistency and batch outputs—train a custom model on ~30–50 approved assets to lock palette, line weight and generate SKU batches for packaging. Midjourney is stronger for high-end hero art and creative variations—use consistent reference images, fixed seed, style tokens, and the same aspect ratio/upscaler to match results. For commercial use, review each service’s paid-tier licensing.

Full side-by-side: Compare Midjourney and Leonardo AI