In a medium sized bowl combine the lemon juice, olive oil, balsamic vinegar, smoked paprika, dill, oregano, garlic, salt and pepper. Add the salmon and toss well, making sure the salmon is completely coated in the seasonings. Let sit for 10-15 minutes.
Meanwhile, cook the couscous or farro according to package directions.
In a bowl, toss together the red peppers, zucchini, 2 tablespoons olive oil, salt + pepper. Toss well to coat the veggies.
Heat your grill, grill pan or skillet to medium high heat.
Transfer the salmon to the preheated grill and grill for about 3 minutes on each side or until the salmon is cooked to your desired doneness. Remove the salmon from the grill. During the same time, add the bell peppers and zucchini, grill 3-4 minutes per side or until char marks appear. Remove everything from the grill.
To assemble, divide the couscous or farro among bowls and drizzle with lemon juice. Add the grilled veggies, salmon, cherry tomatoes, cucumbers, olives and feta cheese. Dollop with Tzatziki and garnish with fresh herbs.