Some large banks may be re-thinking their commitment to the mortgage business and creating opportunities for a number of mid-sized firms, according to analysts at FBR Capital Markets. Servicing problems and mounting repurchase demands have pushed some large banks to allocate less capital to mortgage banking and slowed their originations, FBR analysts said. This has created an opportunity for smaller players to step up and fill the void while still attaining healthy margins, the company added. FBR specifically pointed to PHH Mortgage, U.S. Bank, Quicken Home Loans, Provident Funding, BB&T and...