Heat grill pan to medium-high. Heat oven to 400 degrees F.
Place a pot of water on stove to boil for pasta. Salt water and cook orzo to al dente.
Brush the eggplant steaks lightly with extra-virgin olive oil and season liberally on both sides with salt and pepper. Grill 3 to 4 minutes for small eggplant and 4 to 6 minutes for large eggplant, turning occasionally, until the steaks begin to become tender but are not fully cooked.
While eggplant cooks, defrost spinach in microwave on defrost setting, 7 to 8 minutes. Heat 1 tablespoon extra-virgin olive oil in a skillet and add roasted peppers and garlic. Squeeze the spinach dry and separate as you add it to the skillet. Season the spinach with salt and pepper and heat through. Stir in olives and remove from heat. Place the eggplants on baking sheets. Top each steak with a few forkfuls of spinach mixture. Spread a few rounded spoonfuls of hummus evenly across the steaks on top of the spinach, covering it completely in a thin layer. Toss the bread crumbs with 2 tablespoons extra-virgin olive oil and parsley. Divide the bread crumbs and scatter them over the steaks on top of the hummus. Bake to brown bread crumbs, 5 minutes or so.
Toast walnuts while you cut up the tomatoes and place in a bowl. Cool nuts slightly, chop and add to tomatoes. Add the zest and juice of a lemon, 2 tablespoons extra-virgin olive oil, feta and oregano. Drain pasta, toss with tomato mixture and season with salt and pepper to taste.