In determining whether rates are not excessive or inadequate or not unfairly discriminatory:
(c) Risks may be classified in any reasonable way for the establishment of rates and minimum premiums, except that no classification may be based on race, color, creed or national origin and classifications in automobile insurance may not be based on physical disability of an insured. Rates thus produced may be modified for individual risks in accordance with rating plans, schedules, individual risk premium modification plans and expense reduction plans that establish reasonable standards for measuring probable variations in experience, hazards, expenses or any combination of those factors. Such standards shall permit recognition of expected differences in loss or expense characteristics, and shall be designed so that such plans are reasonable and equitable in their application, and are not unfairly discriminatory, violative of public policy or otherwise contrary to the best interests of the people of this state. This section shall not prevent the development of new or innovative rating methods which otherwise comply with this act.