Charles Schwab's (SCHW) move to cut trade commissions to zero is likely to spur business model changes at TD Ameritrade (AMTD) and E-Trade Financial (ETFC), Deutsche Bank analyst Brian Bedell tells investors in a research note. Instead of managing "persistent" revenue declines, management teams should seek to leverage their strong operating platforms and loyal customer base into a more diversified retail financial service offering that includes online banking, digital wealth management and investment advisory, argues the analyst. This may require "major" M&A for E-Trade and Ameritrade, while Schwab can likely augment its wider range of offerings organically or via smaller bolt on deals, says Bedell. He still views Ameritrade as the "most efficient acquirer" of E-Trade, but finds it no longer clear that the combination "would create a broad enough financial services offering for the new revenue paradigm." One alternative idea could be an E-Trade combination with a digital banking and wealth management platform, says the analyst, who analyzed a potential merger with Goldman Sachs (GS). Bedell also wonders if Ameritrade will eventually explore strategic alternatives or if 43% owner TD Bank (TD) will eventually seek to acquire a much larger controlling stake in the company.