In medium-sized bowl, stir together tomatoes, olives, mint or basil, garlic, lemon zest, and salt (if using). Stir in balsamic vinegar and olive oil. Let dressing sit for 30 minutes.
In medium saucepan, place freekeh, 2 1/2 cups water, and couple pinches of salt. Bring to boil, reduce heat to medium-low and simmer, covered, until freekeh is tender, about 20 minutes. Drain off any excess liquid. Set aside for five minutes and then fluff with fork.
Slice halloumi lengthwise into four slabs. In small bowl, mix together Italian seasoning or za’atar and olive oil. Brush mixture over halloumi slices. Heat grill to medium and grease grates. Cook halloumi slices until tender and grill marks appear, two to three minutes per side.
Brush pepper and zucchini slices with oil and lightly season with salt (optional).Grill until tender and slightly charred, about two to three minutes per side. Remove from grill. Peppers will likely cook faster than zucchini. When cool enough to handle, slice peppers into strips and zucchini into half moons.
To assemble salad, divide greens among serving plates and top with freekeh, vegetables, halloumi, and tomato vinaigrette.