Drain and rinse the chickpeas thoroughly, then pat them dry.Dice the cucumber and green bell pepper, halve the tomatoes, slice the onion, and chop the parsley.In a small bowl, whisk together olive oil, lemon juice, red wine vinegar, garlic, Dijon mustard, oregano, salt, and pepper.Add the chickpeas, cucumber, tomatoes, bell pepper, onion, olives, feta cheese, and parsley to a large mixing bowl.Pour the dressing over the salad and gently toss until evenly coated.Refrigerate for 10 minutes to allow the flavors to blend.Garnish with extra feta, parsley, and a lemon wedge before serving.