Stir the picante sauce and barbecue sauce in a small bowl. Reserve 3/4 cup for the rice.
Lightly oil the grill rack and heat the grill to medium. Grill the chicken for 20 minutes. Brush the chicken with the remaining picante sauce mixture. Grill for 20 minutes or until the chicken is cooked through, turning and brushing often with the picante sauce mixture. Discard the remaining picante sauce mixture.
Cook the rice according to the package directions without salt. Stir in the reserved 3/4 cup picante sauce mixture and the onions. Serve the rice with the chicken. Garnish with the orange slices and thyme, if desired.
Serving Suggestion: Serve with grilled zucchini and sliced ripe tomatoes topped with chopped fresh basil. For dessert serve pineapple chunks.