In a large bowl, whisk together 6 tablespoons olive oil, 3 tablespoons tomato paste, 6 minced garlic cloves, 1 tablespoon lemon zest (reserve 1 tablespoon juice for the salad), 1 tablespoon smoked paprika, 2 teaspoons onion powder, 1 teaspoon cayenne, 1 teaspoon honey, and salt and pepper to taste.
Add the 2 pounds of chicken pieces to the marinade and toss to coat evenly; let sit at least 10 minutes while you prepare the grill or up to several hours in the refrigerator.
Thread the marinated chicken onto skewers, leaving a little space between pieces for even cooking.
Preheat a grill, grill pan, or skillet to medium-high heat. Place the chicken skewers and the 4–6 ears of corn on the hot grill and cook, turning occasionally, until the chicken is cooked through and slightly charred and the corn is lightly charred, about 10–12 minutes total.
While the chicken cooks, make the feta sauce: combine 4–6 ounces feta, 1/4 cup plain Greek yogurt, 1 grated garlic clove, and a splash of water or olive oil in a blender; blend until smooth. Stir in a pinch of smoked paprika and chili flakes to taste.
Remove the corn from the cob and cut kernels off. In a bowl, toss the corn with the chopped 1–2 avocados, 1/4 cup chopped green onions, 1/2 cup chopped mixed herbs, the reserved 1 tablespoon lemon juice, and salt and pepper to taste.
Serve the chicken skewers with the charred corn and avocado salad and the feta sauce on the side for dipping.