Sprouts packs all the best veg*n food into a small, well-organized place. If you need a veggie staple, they have it. Great selection of refrigerated and frozen items.
If you're from out of town, this is a great stop. If you're a local, I have to be honest and point out that Wiseway is just across the street and has a pretty good veg*n/organic section as well. I want to support Sprouts all the time but if I'm doing my weekly shopping at Wiseway and I'm in a hurry or am shopping after Sprouts is closed, it's tempting to get your shopping done and pick up your veg*n essentials at Wiseway.
One thing Sprouts could offer that Wiseway doesn't have is high quality fresh, organic fruits and vegetables. Wiseway offers some but the quality is poor and I can never find an organic tomato! You mention there is a great organic farmer in the same building and you don't want to compete with her/him. That's very considerate of you. But maybe you could both do more business if you guys entered into a relationship where she rented out space from you for a nominal fee to sell her produce. Possibly a win-win situation.