Bring a large pot of salted water to a boil. Cook the macaroni until just al dente according to the package directions. Drain and set aside.

Heat the olive oil in a large skillet over medium heat. Add the shrimp, scallops, garlic, salt, pepper, and paprika. Cook for about 3-4 minutes, until the shrimp are pink and the scallops are cooked through. Gently fold in the crab meat and cook for another minute. Remove from the heat.

Melt the butter in a large saucepan over medium heat. Whisk in the flour and cook for about 1 minute.

Gradually whisk in the milk and heavy cream until smooth. Continue cooking for 4-6 minutes, whisking frequently, until the sauce thickens enough to coat the back of a spoon.

Stir in the Dijon mustard, garlic powder, onion powder, salt, and pepper. Reduce the heat to low.

Add the cheddar, Monterey Jack, and Parmesan a handful at a time, stirring until completely melted and smooth.

Add the cooked pasta and seafood to the cheese sauce. Gently stir until everything is evenly coated.

In a small bowl, combine the panko, melted butter, Parmesan, and parsley.

Transfer the mac and cheese to a greased 9×13-inch baking dish. Sprinkle the breadcrumb mixture evenly over the top.

Bake at 375 degrees F (190 degrees C) for 15-20 minutes, until bubbling around the edges and golden brown on top.

Let it rest for 5 minutes before serving.