You can use more veggies and less noodles if you like. I've found best flavor results (and less looking around the kitchen for extra bread!) when I keep at least 2 layers of noodles. For the eggplant and zucchini, I usually don't use the outermost slice that has lots of skin, but I do leave the skin on interior slices. For the kale, you could add more layers, but I personally don't like more than one layer of kale in my many trials of this recipe. I do not cook my noodles before adding them to the crockpot; they do get soft enough but it wouldn't hurt to cook a few minutes prior if you wanted to.