Of course there can be a bitcoin FRB. It already exists with the current derivates market. I personally don't think it's a good thing or a bad thing. FRB is subject to abuse, but debt is important to an economy, and I don't believe in a central authority barring private transactions. Of course, I don't believe in a central bank. What we have today is absurd. I'm reading a book right now called The Price Of Time by Edward Chancellor. He describes a debate between the socialist Proudhon and Frederic Bastiat. Bastiat argues the importance of debt to an economy. The socialist notion of the evils of interest was sort of embraced post 2008, which is why we're in this mess.