Why was the size of the polis important?

Like a state, each polis was also involved in international affairs, both with other poleis and non-Greek states in the areas of trade, political alliances and wars. ... The biggest was Sparta, although with some 8,500 km² of territory, this was exceptionally large and most poleis were small in size.

A city-state, or polis, was the community structure of ancient Greece. Each city-state was organized with an urban center and the surrounding countryside. ... The majority of a polis's population lived in the city, as it was the center of trade, commerce, culture, and political activity.

answer; i believe that the correct answer is (agriculture);

the noble might have thought that the system was far because they had lot of things and riches and the serf would have thought that the feudal system was un fair because of the way they were treated.