Frontier models offer full access to their image models as part of the service. With those, you can iterate, and brainstorm, and have pretty granular control - "I want the motorcycle to look sleeker" etc, or "give me an inkpunk style bicycle that almost looks like a hybrid kanji drawing" or other such vague handwaving at the AI.
What's the benefit of a site or tool like this over just using the AI I already have?