Simcity 5 must have an option of privatisation.
To be able to franchise out individual or whole networks of public Hospitals, Railways, schools, power and other public utilities. It could be done by having private companies building infrastructure on public demand with approval by you the mayor. The mayor should also pay a higher subsidy for "added" infrastructure and services.
However, franchising out public services should be considerably cheaper and easier and than paying and building yourself.