I want to see Political Agents in Empire. When your country is a republic you can send agents to another country to spread the idea of democracy like the imams and priests does it with the religion. So you can start a revolution in another lands.

The next good idea is that when there is a riot in one of your regions, you can give the order to execute some of the citizens to show them who is the boss. But there also should be the possibility that this fails and the citizens then becomes really angry.