I've always liked the DesignJoy model where you can subscribe to a designer.
Today, we're dropping a similar model for product and GTM engineers. I think this is going to be a fairly prevalent model with the advent of SDD. This is mainly aimed at early to mid stage startups who are running a ton of experiments and are not yet ready to commit to an engineering team long-term.
The flow: Scope via our AI UI/UX tool & delegate to our network of senior AI-native engineers.
You picked the right model to copy, but look closely at why DesignJoy works, because your flow quietly undoes it. DesignJoy's magic is not the subscription, it is that Brett removed scoping entirely: you drop a request in a queue and a finished thing comes back, same person every time. Your flow, "scope via our AI UI/UX tool and delegate to our network of senior engineers," puts back the two things DesignJoy took out, a scoping step and a variable team.
For an early-stage founder running experiments, the dream is not "AI-native engineers, SDD-powered." It is "I drop an experiment in and it ships by Friday, flat monthly, and I never think about who or how." The closer your promise gets to that sentence, the more it is DesignJoy. The further it drifts into the tool plus the network plus the methodology, the more it reads as an agency with extra steps, which is the exact thing your buyer is trying to avoid committing to.
One question: what is the single sentence a happy customer texts a founder friend? If it is "I subscribed and now my experiments just ship," lead with that and let the AI UI/UX tool and the engineer network be the how, not the what. If that sentence is hard to write, the model is not DesignJoy yet, it is a menu.