A favorite of mine is taking the same "meatloaf*," chopped/ground meat/poultry that could be in a meatloaf or hamburger and layer it with vegetables.
For a lower calorie protein main course, layer with sliced eggplant. It's bulk that fills people up. I like using eggplant when it's in season. I don't bother doing any of the "eggplant preparation" methods, like parboiling or salting. There's no need. The eggplants here in Israel are delicious. If yours aren't, then substitute squash, zucchini, onions, tomatoes, sweet potatoes whatever.
*what to add to the chopped/ground meat/poultry per pound or half kilo
- diced onion small
- tomato paste 2T
- raw egg
- garlic, oregano whatever spices you want