Historiographically speaking, it appears that when discussing art, literature, politics, important figures, there is an emphasis on people who lived in urban centers; I understand this may be due to the nature of sources and literacy, but I was wondering if historians acknowledge this as the case?
It depends. People concentrate in cities; so that's where a lot of things happen. That is as true for historical figures as it is true today.
But it's excessively reductive to think of history exclusively in those terms. Up until a few hundred years ago, the world economy was predominantly agricultural; the study of agriculture, population growth, and how the two are linked is certainly very important. In fact, historically most people, especially everyday people, weren't living in cities.
I'm finding it difficult to elaborate much beyond broad themes; but perhaps an example might interest you. Awhile ago I wrote a long answer on Italian Dualism, and the study of agriculture is important to comprehend that phenomenon. We also had an AMA about the Roman Economy, where it is emphasized that "the Roman economy was an agricultural economy: This does not mean that cities were unimportant, that there was no development or change, or that all non-subsistence activity was nothing but a thin veneer over the mass rural reality. But rather the simple fact that the large majority of the population lived in a rural environment and labored in agricultural employment."