A better way is to do away with the quotas to stop all the gaming around it. Switch to a price-based system by imposing a tariff on a percentage of the salary either on the company or on the worker. This would ensure a certain wage premium for local workers to ease the political pressure. This type of policy is more flexible since the tariff can vary based on the nature of the job. After a certain number of years or amount paid the worker should be eligible for permanent residency to limit the leverage companies have over these individuals.