Where your link to moringa is interesting - Looking at the production of it, it sure doesn't seem like you get a lot of density in a given acre of production. For example, lets compare the nutrients produced from one acre of muringa vs. one acre of spinach (rice/wheat/corn). How many pounds of leaves can you get out of an acre of moringa, and how intense is the labor to get that acre harvested vs. one acre of spinach?
There is a reason that we grow the crops that we do - they can be grown very densely, with the least amount of fertilizer, insecticide, water as possible as those things all take money to provide. There is also a need for the minimum amount of labor to plant, maintain and harvest the crops.