Preheat the oven to 400°F. Line a baking sheet with parchment paper.
Place the salmon fillets on the prepared baking sheet. Drizzle with olive oil and season with garlic powder, onion powder, smoked paprika, salt, and pepper.
Bake the salmon in the preheated oven for 12-15 minutes, or until it flakes easily with a fork.
While the salmon is baking, prepare the toppings. In a bowl, combine cherry tomatoes, corn, diced avocado, green onions, cilantro, and lime juice. Mix gently to combine.
Once the salmon is done, remove it from the oven and let it cool for a few minutes. Flake the salmon with a fork.
To assemble the bowls, divide the cooked brown rice among serving bowls. Top each bowl with flaked salmon and the vegetable mixture.
If desired, sprinkle feta cheese on top before serving.