Blend taco seasoning mix and refried beans in a bowl. Spread mixture onto a large serving platter. Mix sour cream and Neufchatel cheese in a bowl. Spread over refried beans. Top layers with salsa. Place a layer of tomato, green bell peppers, red bell peppers, green onions, and lettuce over salsa. Sprinkle with Cheddar cheese. Garnish with black olives.