I grew chickpeas and lentils only once, they seem to benefit very little from irrigation. They are small plants and finish their season very early. That could be of value if you want to follow them with another crop.
Field peas have been in my garden a few times. I've been a little frustrated with them . . . and saving garden pea for seed, for that matter. Weevils seem to be very happy to get in them and ruin things for me
The supposed "Dry Pea and Lentil Capital of the US" is just about 100 miles south of where I live. Quite a few acres of chickpeas are grown around there as well. That is all dry land farming.
Chickpeas may only yield 500 pounds an acre but they can certainly go over 2,000 pounds per acre. Lentils may yield between 1400 pounds to 2,000 pounds per acre. Where they grow pinto beans in Texas, the people there say yield has "ranged between 900 and 2,000 pounds of marketable beans per acre."
All those numbers just go to show that different crops do better in different years, locations, climates, and with different techniques. Now obviously, I don't live in soybean country. Still, I can have quite a bit of fun growing this, that, and the other!
I grow a little wheat in the garden every year but not for eating. Oh, the chickens get a little; the rest is used just for ornamental purposes