The most important aspect is the skillful management of urban planning by shaping the grid of streets, placing buildings and their mutual relation. Well-designed city will greatly improve economic efficiency which may convert into city income.
Diplomacy and politics:
The governor will face very difficult choices to be made in a constantly changing political environment. Costly expeditions, Pharaoh and other cities requests, military threat and a mixture of different cultures will be a commonplace. A series of wrong choices can cost the loss of trading partners and low interest in the city by settlers. Moreover, the total lack of obedience to the rulers may end up with a civil war.
Religion:
Deity will be able to interfere with daily life but it will be done implicitly. The main aspect of religion will be satisfying the need for access to the places of worship, providing supplies for temples or organizing festivals. Neglecting this sphere may result in a dangerous social unrest on a par with e.g. famine.
Trade:
Trade is the most important element in royal treasury. Without it, it is very difficult for economic stability built solely on taxes. Therefore, in the interest of the player, producing goods for export at prices that will be able to change dynamically depending on the geopolitical situation, will be required.