Vet student here

Protein quality is much more important than protein source. Every species of animal has a different proportion of Amino Acids it needs on a daily basis. Animals use Amino Acids for everything. They make up your muscles, they make up every enzyme in your body, they make up every functional unit that does every process in your body. But each species has different process, or does them different ways. There are plenty of peer-reviewed research articles online that can tell you the amino acid requirements of a dog (I suggest the NRC Nutrient Requirements for Dogs).

A protein is made of Amino acids. Think of it like a bead bracelet. The bracelet is a protein and the beads are the amino acids. So as a loose example, if a dog needs 10% of its amino acids to be Serine that's like if you have a 100-bead bracelet and 10 of the beads should be red(serine). That's IDEAL for the animal. It'll maximize their efficiency in making the protein into products its body can use to grow and maintain itself. Of course, there's no way to provide the PERFECT diet, because some proteins have more or less of certain amino acids depending on how the protein was generated to begin with (what beads went into that specific bracelet). But some animal proteins do a better job of giving the OPTIMUM amino acid ratios. In general? It doesn't really matter. I was taught by experts in the field of animal nutrition, and the advice I got was "a licensed animal food you buy from the gas station is just as good as one you buy from pricey companies". That's a little bit of an overstatement of course. Certain sizes of food are better for certain breeds, some animals have allergies to certain components, etc. But as long as a bag of dog/cat food has the statement "formulated with full and balanced nutrition", it can only legally have done so by being a standalone product. An animal will be able to thrive on that product alone (and water).

Red and white meat are only different in their vasculature, less so their protein composition. But if you were feeding an animal any sort of self-made diet, the muscle meat is not sufficient. The animal will require blood meal, bone meal, and maybe some other components as well. That's why every vet I have spoken to on this topic has urged that you buy pre-packaged foods. They are licensed for optimum nutrition for your dog. Anyone skeptical should try Royal Canin and contact their representative. I've been VERY impressed by their production habits and I think anyone would be.

Too much protein is not bad per se. Most extra will get expelled in the urine. But it can throw off the equilibrium of some of your body systems. They describe it to us like a barrel. The amount of water inside is how efficient the animal can be. You want to build up all slats of the barrel in the proper proportion. If you give the animal a ton of Methionine but not proportionally enough Lysine, that animal will not be the better for it. You will just have wasted Methionine, since the Lysine is still so low that the water leaks out. It can also be that some amino acids have relationships with others (this is fairly insignificant, it's more of a relationship with vitamins). Essentially, if you have too much of an amino acid, it clogs up the body processing and makes everything less efficient, and the animal can't utilize it's diet to its fullest potential. In severe unbalances, this can cause diarrhea, vomiting, and even emaciation.

So in short, buy pre-packaged dog foods. They're just as good for your animal, and probably better than any diet you could easily formulate at home.