Hmmm. I replied, but had a browser crash, so sorry if two responses show up.
Unless you already have a lot of domain knowledge in the market you're targeting, this seems risky. What about doing it the other way around. Partner with someone in that market to develop a more fully functional product with the intention of marketing it more widely once it's been road tested? It will be longer before the product hits the market, but it will be a more complete product.
Maybe I'm a little gun shy because of the times when management tried to roll a proof of concept into production instead of concentrating on making sure the software does what it's supposed to do. This is how we wound up with countless clunky applications with business logic in button click events on the main form.