Chickens/poultry should bring joy, and when they wind up being more work that's difficult for us to manage, then that's definitely frustrating.
It seems to me your frustrations are regarding rats. Rats come because there's food, and because they can get to it.
You can buy those treddle feeders, although I don't know that they make them for quail. I think your ideas of digging down and putting a 1/2" hardware cloth skirt will help tremendously.
If you need help, check your local newspaper's classified section. Sometimes there's an old fart looking for something to do, and would help for cheap, rather than "hiring" a professional. We once found a high school group looking to do anything to raise money to go to Japan. We hired three of them to move a huge pile of gravel from one side of our yard to two acres away. They did it!
After you get that all fixed up and rat-proofed, you'll feel better and they should be back to enjoyable instead of so frustrating.