In an effort to accommodate the increasing air traffic demand, research is conducted to increase future airspace capacity. In addition to the growing demand, new forms of air transport are entering the market. Although a distributed control strategy seems unavoidable to cope with the introduction of Unmanned Aerial Vehicles and Personal Air Vehicles, research on how this distributed control should be organized has not yet reached consensus. Prior research has demonstrated that structuring airspace into layers results in a lower conflict rate compared to an unstructured airspace. The principles of aircraft dispersion and relative velocity reduction in the layers have a positive effect on airspace capacity, and these principles are further explored in this research. In a large-scale simulation experiment with a mix of different Personal Air Vehicles, the value of defining lateral zones in a departure/arrival area was investigated. By comparing the zones concept with an unstructured airspace concept, it was found that structuring the airspace can act as a conflict prevention mechanism. The added value of the zones becomes more apparent at higher traffic densities. Different zone configurations were evaluated and compared. Simulation results show that a configuration with a higher number of zones results in the lowest overall number of conflicts, at the cost of a slight efficiency loss.