I have been thinking about this for most of the winter, and now it is spring, and time to start doing something about it.
I am very interested in foraging. I have listened to speakers who I consider logical and sane, and believe that there are myriad plants and even animals out there that are edible, and yet rarely eaten these days. One good example is goosefoot. Goosefoot is a non-native weed that was actually brought to the US and cultivated as an edible food. For some reason, no one farmed it any more, and now it grows wild as a weed.
I am interested in making something between 50-75% of my calories come as forged food. Obviously I can't really do that until the weeds begin popping up here. I'll begin with a small amount and work my way up from then if all goes well.
It is also said that in nature, fat and protein are the least available foods, so people are biologically motivated to eat as much of the stuff as possible. This "hording" of fatty foods is natural, but leads to overweight people in an environment where fatty foods are available in vast amounts. The way to lose weight is to avoid this kind of food. In nature, it is hard to find fat, and also sugary food. The bulk of edible food is very low calorie and high fiber. Often the fiber necessitates what we would call "processing."
Dry beans can only be eaten if they are either sprouted or cooked. Some kind of processing must occur. Many beans contain toxins, and cannot be eaten in large amounts without processing. Some vegetables are better, or more bio-available if cooked. A good example is the bio-availbility of lycopine in tomatoes.
The cellular walls of many foods must be lysed prior to eating because it is lysing that allows the many nutritional properties to move from the cell walls to the viola of the intestines. So, often it is better to cook a vegetable than to eat it raw.
I think you just need to read up on each vegetable to see how it is best prepared.