Place chicken in a deep pan. Toss with 2 TBSP olive oil, remaining smoked paprika, 1/2 tsp kosher salt, 1/2 tsp pepper, cayenne pepper and garlic powder and 1/2 of the chopped herbs. Cover with plastic and let rest for 30 minutes while you prepare the vegetables and the grill. Place chopped vegetables in another pan. Coat well with 2 TBSP olive oil, 1/2 tsp kosher salt, 1/2 teaspoon of pepper. Keep onions intact- do not separate into individual rings. Set aside.
Pre-heat your grill to 400 degrees. Wipe down grill grates with paper toweling soaked in vegetable oil.
Place chicken on the grill and cook for 10 minutes. Flip and cook until the internal temperature reads 160-163 degrees. About another 10-15 minutes. Place chicken in a clean metal pan or baking sheet. Cover tightly with foil and let rest for 10 minutes.
Place vegetables and nectarines on the grill over the indirect heat, but near the chicken, and let char slightly on each side. Flip after 3 minutes to have grill marks on both sides. Remove after 5-7 minutes once peppers have softened slightly. Asparagus may need only a few minutes to cook. Use a spatula to remove onions and fruit to keep them intact as much as possible. Use tongs to remove asparagus and peppers. Place on a cutting board and chop into large pieces. Cut nectarines into wedges. They will be slightly jammy. Cover and keep warm until bread is finished.
Brush naan or pita bread with olive oil . Grill for 1 minute on each side until grill marks are achieved. Slice into long strips and sprinkle with flakey sea salt.
To Serve: Slice chicken on the diagonal. Place a large smear of labneh on each plate, sprinkle with remaining herbs. Top with vegetables and sliced chicken. Pour vinaigrette over top of each plate.