01 - Combine blueberries, balsamic vinegar, honey, lemon juice, Dijon mustard, salt, and pepper in a small saucepan. Bring to a simmer over medium heat, stirring occasionally, until blueberries burst and sauce thickens, 8 to 10 minutes. Mash berries gently with a spoon. Remove from heat and strain if a smoother glaze is desired. Set aside.
02 - Preheat oven to 400°F. Pat salmon fillets dry and season both sides with salt and pepper. Heat olive oil in an oven-safe skillet over medium-high heat. Sear salmon fillets, flesh side down, for 2 to 3 minutes until golden. Flip fillets, brush generously with blueberry glaze, and transfer skillet to oven. Bake for 8 to 10 minutes, or until salmon flakes easily with a fork.
03 - Bring vegetable broth and olive oil to a boil in a medium saucepan. Stir in couscous, cover, and remove from heat. Let sit for 5 minutes. Fluff couscous with a fork and stir in lemon zest, lemon juice, parsley, dill, salt, and pepper.
04 - Divide couscous among plates. Top each serving with a glazed salmon fillet. Spoon additional blueberry glaze over salmon, if desired. Garnish with extra herbs and lemon wedges.