Chicken stock (or any stock) is made from bones; that generally means backs, necks, and carcasses - which are generally the cheapest "cuts" because they have almost no meat and aren't useful for much else. Sometimes, if you approach a butcher with high turnaround, you can get them at a steep discount, well under $0.50/kg, because they just end up throwing most of it out.
If you add any meat whatsoever then you are essentially making a broth, not a stock. I repeat, stock is just bones, simmered long enough to denature all or most of the collagen, usually no less than 8 hours.
I find that most people (myself included) prefer brown stocks, so roast them first. You can sauté, but it's not as effective as a slower roast because the heat doesn't really penetrate far inside the bones. It also helps to cleave the bones before simmering (after roasting) to expose the marrow; it makes for easier extraction, although some people don't like the marrow flavour as much.
The least expensive way to add more flavour is probably to add the dry stock mix or bouillon cubes filled with salt, MSG, and other flavour enhancers. Of course it won't really taste like a homemade stock if you do that. If you want a good stock then the traditional way to flavour it, which is also very inexpensive, is to use a mirepoix, which is just a 2:1:1 ratio of chopped onions, carrots, and celery. You add this about 1-2 hours before the stock is done and remove it before clarifying.
Going up the cost/taste scale is a bouquet garni, which, although the herbs that go into it can get fairly pricey, the amount you use is minuscule, so it costs practically nothing if you have other uses for the remainder of the herbs.
Don't even think about trying to put "expensive cuts" of meat into a stock to improve its flavour. You'll just be wasting the meat, which loses most of its flavour when boiled/simmered, and turning your stock into an unsalted broth, which makes it less versatile and generally perceived as blander.
Now if you want to make a soup with better cuts of meat, that's great; in that case, the texture matters, and I'll occasionally poach some boneless thigh or breast meat to use in a chicken soup (made from the aforementioned stock) for the sake of convenience. But I emphasize that this is done after the stock is made. The soup will also have other ingredients added such as chopped vegetables and of course plenty of salt.
Stock isn't supposed to have an exceptionally complex flavour, that's why it's called "stock" - it forms the base of other dishes such as soups, broths, or anything that calls for flavourful liquid (like a risotto). Focus on making a good clear stock from just bones and mirepoix; it gives the best result because you tweak it later according to how you use it, and it costs you almost nothing besides the energy it takes to keep the pot heated.
I very quickly found nutritional information for storebought (Swanson) chicken broth and chicken stock. As you'd expect, neither one contains all that much protein. The stock does contain substantially more: 4g per cup compared to 1g - this should also be expected, since stock has some gelatin in it, and gelatin is mostly protein.
Of course, it's commercially made; I imagine you'd be hard-pressed to find good nutritional data for homemade stock and broth.
Best Answer
Edible? Absolutely yes.
Flavorful? ....you should taste it and tell us. Seriously, don't serve a meal to anyone, yourself included, until you've tasted it and it tastes at least decent. (Not trying to be snarky here, that's literally the best cooking tip I was ever given)
Nutritious? Probably somewhat--that chicken muscle is primarily protein after all.
Generally, soups are made with bones because bones can't be used for anything else, so it's more economical to get soup-flavor from bones (making the stock), then use meat for texture and to add variety to the liquid. I was taught to put meat into soups in the last hour of cooking. Many recipes I've seen call for taking out the whole pieces of meat and shredding it or pulling it before serving it in the soup.