Preheat the oven to 400°. Line 2 large rimmed baking sheets with parchment paper. In a large bowl, whisk the eggs with the milk. Stir in the panko, garlic, parsley, oregano, basil, 1 cup of the Parmigiano-Reggiano, 2 teaspoons of salt and 1/2 teaspoon of pepper. Add the ground turkey and gently knead to combine.
For Kids Form two-thirds of the meat mixture into thirty-two 1 1/2-inch meatballs and transfer to one of the baking sheets.
For Adults Knead the sausage and red pepper into the remaining meat mixture and form into thirty-two 1 1/2-inch meatballs. Transfer to the second baking sheet.
Brush the meatballs with 1 cup of the tomato sauce. Bake in the upper and lower thirds of the oven for about 40 minutes, shifting the pans halfway through baking, until the meatballs are cooked through.
Meanwhile, in a pot of boiling salted water, cook the pasta until al dente. Drain the pasta and return it to the pot. Add the remaining 5 cups of tomato sauce and cook until heated through, tossing well. Spoon the pasta into 2 large serving bowls; add the mild meatballs to one and the spicy meatballs to the other. Serve, passing additional cheese at the table.