I wonder why everyone is downplaying the moral and technical hazard of having a single entity controlling all the issuance and payments in a country? At least right now if some bank sucks I can take my money elsewhere.
If the financial system is a tree, the root node is the central bank, the second level nodes are the private banks and in the next level are the business and households.
By the way, this perspective makes clear that banks are not "only another business" as we hear sometimes.