After the events of the last two years, everyone agrees that change is needed. However, opinions differ about the kind of change we need. First, there are those that see the complexity of the financial system as the root of the problem, and therefore propose to constrain finance much in the way it was until the 1980's.
Some suggestions along this line are narrow limits on the activities of banks, splitting supposedly “safe” banks from banks engaging in capital market activities, or constraining specifications of financial products to those pre-approved by authorities.