Corn is not all that great a food. Just energy for the most part. If you hillside is like our swiftly sloping land then it is not very good for growing corn either. A bit of a climate issue too.
What I find is that it is far better to divide the land up for managed rotational grazing, improve it with alfalfa, clovers, trefoil, chicory, millet, brassicas, highly palatable grasses and then graze livestock on it. We graze pigs, ducks, chickens and geese. We feed them no commercial grain/hog feed. We supplement with dairy which makes up about 7% of their diet. Pasture makes up the vast majority of their diet replaced with hay in the winter.
With just a half acre you could do five pigs through the warm months quite nicely.
Cheers,
-Walter Jeffries
Sugar Mountain Farm
Pastured Pigs, Sheep & Kids
in the mountains of Vermont
http://SugarMtnFarm.com/