This is not an argument against another Axe, but the test file suggests that we have quite a bit of time before barbs invade. Consider that, usually ~T30, the human will only have one city, and that Immortal barbs are not as aggressive as Deity.
Barbarians will start to enter border when most AIs has 3 cities, I guess it's around 40~50. It will be quite severe since we have large empty space in south and North for barbarians to spawn, it won't be archers only, we should expect axes.
We should have enough gold to research Aesthetics and most of Literature. Moreover, the capital unhappiness has dropped by ~T50, so we can easily whip into TGL and NE. Currency will be worth ~4GPT, but I suppose there will be a good amount of fail gold the AI will stockpile from all the ancient wonders. So I will think about this some more.
As I already said, TGL gives more than currency for sure things, like beakers and GPPs (this is an uncertain value, could be 1 extra GS or nothing), but Currency offers benefit for something uncertain, or in another word, flexibility. Delaying TGL also has the advantage of more worker forces.
Will look into this.
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The AI automatically run a 20% espionage slider when at war.
Early testing shows that Rue de Paradis can 2-pop whip a Settler or Worker on the turn that it has 9/10

. I strongly suspect a Worker will be the better build, with a slower Settler coming from the capital.
Starting Point will build a Settler/Worker more slowly than Rue de Paradis, even if we put the copious Library OF into this. But a slower Settler isn't a bad thing if the Wheat isn't already improved.