I live in Addis Ababa next to one of the small markets you describe an interact with the market people quite a bit. I think what you are planning can work. In fact, I think it is bridging a critical gap in what is currently happening in Addis: A building boom, that is completely dominated by megalomaniac concrete dreams, completely ignoring city micro climates, air circulation etc, energy shortages, let alone the interest of all the small traders and producers that keep the city running and alive. It might also make sense to train small-scale local construction contractors in adapted-building technologies and link them up to the people running the markets. Just a thought. Hope you make it further, Addis needs you!!