In establishing categories of local governments, the remuneration commission—
(a) must have regard to the following criteria—(i) the size, and geographical and environmental terrain, of local government areas;(ii) the population of local government areas, including the areas’ demographics, the spread of population serviced by the local governments and the extent of the services the local governments provide; and
(b) may have regard to other matters the remuneration commission considers relevant to the effectiveness, efficiency and sustainability of local governments.