Well you can just grow chickpeas. “High yield” with existing varietals, heirloom or otherwise has more to do with your climate conditions and soil. Along with how much space and time you can dedicate to it.
If you’ve never gotten a serious chunk of your food from gardening or farming, it takes quite a lot of work and room. You aren’t doing it on a small back garden. My grandfather had a small subsistence farm thing going for a long time, feed his 10 kids on the cheep. It provided most of the produce, carbs and a big chunk of the meat/eggs and dairy for my mom’s family growing up. And then a lot for my family after he retired (we was broke).
It was about a half acre to an acre of heavily rotated plots. Along with multiple out buildings for the animals. And practically speaking a full time job for multiple people. Largely my mom and her siblings.
Like I said you don’t need a new variety for that. We have that. And no new variety is going to change how it works.
At home the issue is more milling. IIRC chickpeas and other peas can usually be ground in a food processor or blender. Which isn’t the case with grains. But other types of peas and beans aren’t neccisarily suited for use as a neutral flour, as they’re often pretty strongly flavored. Green and yellow pea flours taste pretty strongly of peas, black bean flour is used for black bean things.
That seems to be why gram is more of a thing. It’s more flexible down to it’s fairly neutral flavor. I hear white bean flour is quite good as well. Which makes sense they’re have a pretty mild, savory creamy thing going on.