My Mom's Awesome Macaroni Salad (enough to feed a crowd!)

Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally until cooked through but firm to the bite, 8 minutes; drain. Rinse macaroni with cold water until chilled; drain. Mix mayonnaise, white vinegar, seasoned salt, sugar, garlic powder, and black pepper in a large bowl with a whisk until smooth. Stir tuna, baby shrimp, cucumber, and sweet onion into the mayonnaise mixture to coat ingredients completely; add chopped eggs and stir. Pour chilled macaroni into the bowl and stir; top with sliced eggs. Garnish salad with paprika. Cover bowl with plastic wrap and refrigerate at least 1 hour to overnight before serving.