Such application shall include a design plan showing the character of the development that is proposed for the requested site. The design plan shall include: locations of principal and accessory structures, typical building elevation drawings, parking areas, traffic access and circulation, and open landscaped areas. Such supporting materials shall clearly demonstrate the concept, design, and uses of development. The submission shall also include any statements the applicant may consider appropriate relative to the necessity or desirability of development, its harmony with adjacent development, its conformity with the Comprehensive Plan, other community plans, and the reasons it cannot be developed under other zoning regulations.