In addition to specific authority granted elsewhere in this chapter, the director may make, amend, and rescind rules, forms, and orders as are necessary to carry out this chapter. Such rules or forms shall include but need not be limited to rules defining any terms, whether or not used in this chapter, insofar as the definitions are not inconsistent with this chapter. The director may classify commodities, commodity contracts, and commodity options, persons, and matters within the director's jurisdiction. No rule or form may be made unless the director finds that the action is necessary or appropriate in the public interest or for the protection of the investors and consistent with the purposes intended by the policy and provisions of this chapter. The director may, by rule, establish a schedule of reasonable fees to carry out the purposes of this chapter, such fees to cover the estimated costs of enforcing this chapter.