Preheat oven to 350°F (175°C). Spread rinsed farro on a baking sheet and roast for 15-20 minutes, until fragrant and slightly golden. Set aside to cool slightly.
Heat 2 tablespoons olive oil in a large skillet over medium heat. Add cabbage, garlic, cumin, oregano, and red pepper flakes. Cook for 10-12 minutes, until cabbage is tender and slightly caramelized, stirring occasionally. Season with salt and pepper.
In a large bowl, combine the warm farro, sautéed cabbage, cherry tomatoes, chickpeas, olives, and pickled red onion (if using). Stir to mix evenly.
Make the dressing by whisking together the lemon zest, lemon juice, and olive oil. Season with salt and pepper. Pour the dressing over the mixture and toss until coated.
Fold in the crumbled feta and herbs. Taste and adjust seasoning as needed.
Serve warm or at room temperature. Garnish with additional feta, herbs, or a drizzle of olive oil.