The commissioner shall disapprove any such contract if he finds that it:
(a) Subjects the insurer to excessive charges; or
(b) Is to extend for an unreasonable length of time; or
(c) Does not contain fair and adequate standards of performance; or
(d) Contains other inequitable provisions or provisions which impair the proper interests of policyholders of the insurer.
(Added by Stats. 1963, Ch. 1772.)