I wonder how he manages to balance all these elements. Even in much simpler games balancing the strengths and weaknesses of all the actors can be very difficult. With so many interlocking factors it seems it would next to impossible to avoid inadvertently making one tactic or actor too powerful.
For example, in the early Civ games the optimal strategy was to just build up to chariot technology and then go 100% on the offensive.
There are a lot of releases, and fairly often; I've had versions go "out of date" on me within a week of its release. The forums are very active, and when they say something is unbalanced or broken, it tends to get fixed. Some things are not serious game-breakers, even if they are mildly broken (see: elephants in the versions that Boatmurdered used), and those tend to stay in until it becomes a pain to deal with.
Basically, it's just trial-and-error. But it makes for an interesting game, because you're never quite sure if everything will work as expected.
For example, in the early Civ games the optimal strategy was to just build up to chariot technology and then go 100% on the offensive.