In our own case at the RBA, the decision-making body includes a majority of non-executive directors who generally bring a wide range of expertise and experience from outside the specialised field of central banking. There is, from time to time, discussion about which set of arrangements is best, and reasonable people can and do differ on this.
But experience seems to be that several types of decision-making structure can work acceptably well. The question 'who is on the board?' is important, but perhaps not as important as the questions 'what are the board's goals?' and 'does the board have the tools, and the independence, to pursue them?'