Having the airports for trade later in the game is inportant I have learned. I create at least 1 airport on every continent, this way you can airlift the freight to it then move the freight over land. Pretty basic but I am learning.
I will not bore you with the math (I've put it in other threads anyway
), but here is a good general rule if you want mongo gold for your freight: After Flight, do NOT deliver freight until both the source and destination city have airports. You lose 33% of your trade after Flight, but get a 50% bonus for the airports. So get Radio on the same turn as Flight (Double advance), have your key airports pre-started, and make sure they finish on the next turn. The increase in gold and science initial bonuses alone will
more than fund the rushed airports.
Eyes of Night came up with a clever idea when we were toying around with all tech on prince by 1000bc. To increase his trade bonus,he built up a nice big city with all the goodies in it.Then he let the ai capture it.Yes some improvements are lost but still that city is much better than the typical AI city.That is about the only way to get an AI city "up to snuff".
When speed speed speed is not as important (e.g., non-GOTM games), it is pretty easy to steer the AI to airports if you create/remove the right threats, and give the advances or "let" them get captured/traded from a rival civ. When speed is important, even at Deity the AI does not really have the time to build, esp. since it always senses the human breathing down its neck and won't perfect as much.
Last fall, I tried a similar thing, but nixed the idea when I determined it was completely impossible for the AI to take a city by force that kept both the Airport and the Superhighway. I wanted the AI to have both, but discovered in the process that the loss of improvements is not random... there is a pattern, which allows one of two sets of improvements to be kept... one set excludes the other, and so for me I dropped the idea, and instead use gifting, seeding, and threats/friendliness to steer their own construction. But in fast games, this has almost no efect. In GOTM 8, my Ally (Sioux) has been making Superhighways for hundreds of years, and times have moved on such that it no longer matters because he has no sewer and is stuck at size 12 anyway. So now I have my own cities just booming in the right physical locations to start max trading in about AD 1.