Preheat oven to 350°F. In a medium bowl, mix ketchup and barbecue sauce until smooth. Set aside.
In a large bowl, combine ground beef, crushed crackers, eggs, onion soup mix, salt, pepper, garlic powder, onion powder, and half cup of the sauce mixture. Mix gently until just combined.
Press the meat mixture evenly into a greased 9x13 inch baking dish. Spread the remaining sauce over the top. Bake for 30 minutes.
While the meatloaf bakes, cook macaroni in salted boiling water until al dente. Drain well.
In a large bowl, whisk together milk and condensed cheddar soup until smooth. Stir in 2 cups of the shredded cheese. Add the cooked macaroni and mix until evenly coated.
Remove the partially baked meatloaf from the oven. Spread the macaroni and cheese mixture evenly over the top. Sprinkle remaining shredded cheese over the casserole.
Return to oven and bake for 18 to 20 minutes, or until cheese is melted and lightly golden. Ensure internal temperature of meat reaches 160°F.
Let the casserole rest for 10 minutes before slicing and serving.