When reviewing a site plan, the Planning Commission may act upon the plan submitted to it or may act on its own initiative in recommending the approval of a site plan. In considering any site plan, the Planning Commission and Zoning Hearing Board shall endeavor to assure safety and convenience of traffic movement both within the site covered and in relation to access streets, harmonious and beneficial relationships of structures and uses on the site as well as contiguous properties. To this end, the Planning Commission and City Council may limit vehicular access. Special consideration shall be given to vehicular access to and from arterial roads.