Preheat the grill to medium-high heat. In a small bowl, mix together the olive oil, garlic powder, onion powder, paprika, salt, and pepper. Rub this mixture all over the chicken breasts.

Grill the chicken for about 6-7 minutes on each side, or until fully cooked and the internal temperature reaches 165°F. Remove from the grill and let it rest for a few minutes before slicing.

While the chicken is resting, heat a skillet over medium heat. Add the diced pineapple and brown sugar. Cook for about 5-7 minutes, stirring occasionally, until the pineapple is caramelized and golden brown. Remove from heat and stir in the lime juice.

In a bowl, combine the caramelized pineapple, red onion, and cilantro. Mix well and set aside.

To assemble the rice bowls, divide the cooked rice among four bowls. Top each bowl with sliced grilled chicken, a generous scoop of the pineapple salsa, and avocado slices. Serve with lime wedges on the side.