In a large bowl, combine chickpeas, eggplant, tomatoes and 1/2 cup basil. In a small bowl, whisk together vinegar, 2 tbsp oil, honey, pepper flakes and black pepper. Pour over chickpea mixture and set aside to marinate for 30 minutes.
Cook spaghetti according to package directions. Drain, reserving 1/2 cup cooking water.
Meanwhile, in a large skillet, heat remaining 2 tsp oil on medium-high. Sauté garlic for 1 to 2 minutes. Add spinach and sauté for 2 minutes. Reduce heat to medium and add chickpea mixture; cook for 10 minutes or until eggplant is softened. Slowly stir in reserved cooking water.
Return chickpea mixture to large bowl along with spaghetti. Stir in feta cheese. Top with remaining 1/3 cup basil.