They have scratch mix, scraps from the kitchen plus i usually give them a can of corn and a cucumber and zucchini(they go nuts over it) cut up. Lettuce if i have some to spare, tomatoes. Actually whatever salad stuff i have. They usually get a salad a day. Also the ends of the bread from inside too. I like to sit outside and handfeed them. They also get the forage in the horse paddock and house yard during the day when the dogs are inside.
Scratch mix is oats and corn, yes? I'd say the diet needs to have more vitamins, minerals, protein and even a little oil, like from flaxseed meal.
Mother Earth News has a couple of articles on feeding your flock from the homestead if you want to go that route. Countryside Organic layer feed ingredients are another really good guideline for optimal nutrition.