I am growing this year several grains, for the first time, and beans (but that is not my first time).
Barley and rye are ok to harvest, and strong plants to grow. With oats, you must choose a hullless variety, otherwise it's too much work. Dehulling is ok when there is not so much to remove, that it comes out easily when you crush it and blow in the wind.
These grains stand very well frosts and dry weather, and even poorer soils (but produce much better in richer soils).
Grow these grains and wheat, so that you can ground the grain into flour and make your own bread!
Corn yields more grain per plant, and is much more easy to harvest, but it's not as nutritious and is a bit more picky while growing, demanding humidity and a fertile soil. But definitively grow a bit: you will love to harvest and roast those corn cobs.
Amaranth grows well but tall (quinoa even taller), and yields not as much grain as wheat, barley and rye. Its quite dry resistant but needs hot weather, and demands that you shake/scrub the heads to let the grain fall. There is always some seed that falls down, but you don't worry with that. Its easy to harvest, no dehulling to be made, but it requires some time to scrub the seed heads. Afterwards just blow in the wind. Advantage: is a very rich food.
Quinoa I am still waiting for the harvest but I know it requires pre-treatment to remove the saponins, by extensive soaking and washing. Its easy to grow but very tall plants. Overall, quinoa and amaranth yield much less per acre than conventional cereals. But they are the only ones being a complete protein. I am really happy to eat my own cultivated amaranth
I am trying buckwheat, millet for the first time. And I plan for sorghum and teff for next year. I think millet is the easiest to harvest and is quite dry resistant. Its also good food, very light but nutritious. Millet seems easy to grow, but my buckwheat plants are nott growing that well (I think they need a poor and well drained soil). Buckwheat is also a complete protein.
Cowpeas is easy to harvest and to grow. My number one choice for beans.
Most beans are also easy to harvest but the plants are not as resistant as cowpeas.
I also grow chickpeas but they required warmer and dry weather. Its not pleasant to harvest them (as the lentils), because these both yield only one or two seed per pod. They yield about half of cowpeas and beans per acre. The pulses are a easy and basic homestead staple.
I never tried lima beans or other types of
perennial beans. Never tried rice.
How much area to grow? I calculated to need at least (for 1 entire year) to grow about 200 m2 of grain, and 200 m2 of pulses. Both areas combined would be about 1/10th of an acre.
I must say potatoes yield much more mass per area, than grains and pulses. But potatoes have less calories than grains.