Don brings up a good point that you need to ask yourself. Does the community really need the product you are going to market? If you do your research and determine that there is a need, go forth and have a ball!
Many times banks roll out programs without doing the important market research. This is when you will hear your regulators say...Nice try doofus, how about the results? (Ok doofus they probably reserve for drinking sessions when you leave..but it's sometimes implied)
If you have success outside of your AA's due to the locality that the partner is serving you shouldn't need to expand your AA. Unless your inside/outside ratio is horrible now, and you're expecting a very significant change due to the product success, this shouldn't be a worry for you. I actually receive credit for work I'm doing outside of my AA's because I'm the only bank willing to make the effort to serve these folks. I don't expand my AA's to cover their areas because I can't reasonably serve all of the area and don't have branch locations there, but the services I am providing are so needed I get CRA credit anyhoo.
This might be the case for you as well if you document how desperately the services are needed (ie Is anyone lending there?) and how you stepped up to the plate to provide them.
Good luck!!! Sounds like your heart is in the right place.