The health insurance plan provided for in this chapter shall be designed by the State Employees’ Insurance Board to provide a reasonable relationship between the hospital, surgical, and medical benefits to be included and the expected hospital, surgical, and medical expenses to be incurred by the affected employee and retiree and dependents and to include reasonable controls, which may include, but are not limited to, deductible, copayment, coinsurance, and other cost containment measures to prevent unnecessary utilization of the various hospital, surgical, and medical services available and to provide reasonable assurance of stability in future years for the plan.