Theocracy is a form of government in which God or a deity of some type is recognised as the supreme ruling authority, giving divine guidance to human intermediaries that manage the day to day affairs of the government who claim they are in power due to the divine will of their God or gods. Famous theocracies throughout history include the Pharaohs of Ancient Egypt, Ancient Greece and the Roman Empire where Emperors were often declared gods.
Yes, theocracies have many good points
Almost every major religion has a concept of a theocracy as part of its doctrine.
Theocracies create a sense of unity within society
A theocracy gives all citizens something to be united over.