If you're building this as a business, then you need to stop coding and get selling right now. Building a landing page is 0% of that, talk to customers, figure out what they want. Writing code first will not advance you at all towards a business goal.
It's fun and I don't think LLM with all the uncertainty would fit as well since you want to cover the whole input space.
Hope to charge 99$ or something per year for it but I don't know if anyone would pay for it :)