How are the lungs designed in human beings to maximize the area for exchange of gases?

The structure of the lung is as follow:
In each lung the air passage is divided into smaller and smaller tubes, named as bronchi which divide into bronchioles. These bronchioles further terminate in balloon-like structures, called alveoli . These alveoli provide maximum surface for exchange of gases and occupy less volume. They are further connected with veins and arteries to facilitate exchange of gases.