Here we have a commentary moments from a Civilization IV playthrough recorded by YouTuber Chris67132. Some highlights below are more game-specific, and others have more direct cross-game applicability, but all showcase the type of thinking and commentary we want to see here. Topics covered include settlement priorities, ally choice, and a situational short and early war. I've inserted a short discussion of how the Slavery civic gives a "rule-breaking" capability that enables exchange of normally nonexchangeable resources, which requires a paradigm shift in evaluation.
In this first clip, we hear that Chris is not a huge fan of the Babylonian bowman on deity difficulty. The bowman is a unique archer replacement, an early defensive unit. An early defensive war will seriously severely hamper the player's opening development, even with the bowman. Chris does later concede that the bowman is much more effective at defending against barbarians than an archer:Chris prioritizes settling the richer possibly-contested land first before filling in the land closer to the capitol:
Chris has to choose which of the two known neighbors on this continent to be friends with, since they are already working on disliking one another. Zara, the AI leader of Ethiopia, often makes for a loyal ally:
Zara is expanding towards Chris, who needs to settle the relatively rich intervening territory quickly. Chris more-or-less finalizes his decision to be friendly with Zara as a trading partner, partly because the proximity enables open borders and trade routes. Hannibal will likely become an enemy to target on this continent:
Overexpanding and unbalancing your empire is bad, and not just in Civ IV. The specifics vary from game, be it Civ, Starcraft, chess, go, or something else, but there are frequently drawbacks to reckless growth. In this Civ IV case, the risks are often tied to the opportunity cost of putting production and food into settlers instead into infrastructure and population growth. A player's many underdeveloped cities can cause an empire's budget to run a deficit, ultimately reducing science income if in the red with a depleted treasury. A large empire requires more units to defend, suffering from increased border surface area, a problem made even more dangerous by having built more settlers and fewer military units:
Pop growth in this early stage of Civ 4 is checked by the Slavery civic. Slavery is unlocked early and is extremely valuable because it allows one to "break the rules" and turn food (in the form of a sacrificed citizen) into production. Such rule-breaking tools are often important to the games that have them. Enabling an exchange of normally-unexchangeable resources forces a major reassessment of their value. Here Chris elects not to construct an extra worker because his cities' population growth is not outpacing the rate at which his workers create improved tiles:
Chris catches first sight of Carthage's borders, and also spots a settler angling for a city spot Chris wants. In this situation, Hannibal has only four cities and may even lack access copper with which to build axemen. The importance of contesting the city spot and Hannibal's relative weakness in this particular situation combine to entice Chris to declare war and capture the encroaching settler before it can plant a city:
Blocker cities are important, whether against humans or AIs. In this case, Chris adjusts the location of his southern city to reduce the chance that his cap will be directly targeted by Hannibal. Chris shortly produces some axemen and techs towards his unique archer to garrison the new intended blocker city: