Cook the rice according to package instructions, then mix in lime juice, sugar, cilantro, and salt.
Mix corn, black beans, red onion, tomatoes, lime juice, and garlic powder to make the salsa.
Combine spices in a small bowl. In a large skillet, heat oil over medium-high heat, add shrimp, sprinkle spice mixture, and cook until pink, about 3-5 minutes.
Assemble bowls with rice, corn salsa, and cooked shrimp. Top with desired optional toppings.