It sounds like you have a good base to start on (surveys, photos, brand research).
What are you looking at doing with the advertising, etc? A retro look might be a good idea, but how will it fit in with your larger plans.
Also: what is the current market for this product? Where do you want to take it? I can see a potential market with young professionals that have heart-burn on top of everything else in a busy life. I might just think that because it would be a more interesting project though;)
It reminds me though: try to sketch up a profile of your ideal users. Go deeper than just stats though. Give the user a name, hobbies, profession, photo. That way you can start talking about them as a real person, not just a column of data. It helps!