The Commission may, upon the informal written request of the registrant, and where consistent with the protection of investors, permit the omission of one or more of the financial statements herein required or the filing in substitution therefor of appropriate statements of comparable character. The Commission may also by informal written notice require the filing of other financial statements in addition to, or in substitution for, the statements herein required in any case where such statements are necessary or appropriate for an adequate presentation of the financial condition of any person whose financial statements are required, or whose statements are otherwise necessary for the protection of investors.