I notice many players have problem with keeping AI happy. So, I would like to highlight a small trick that helps slightly to keep AI happy. I had Gracious and Polite AI in GOTM20 even though I keep breaking MAs.
The trick is that whenever you sell something and the AIs couldn’t afford it. Instead of just settle for less (i.e. just sell it for whatever they have), why not just give them gold to make up the difference.
As an example, say you can sell Gunpowder at 1400gc or the equivalent of it. But AI can only offer 20gpt. So, instead of just accepting that. First give AI 800 gold then follow by a 20gpt+800gc for gunpowder trade. I can get the AI relation gift bonus (worth 10) virtually to last to infinity by doing this since the AI never have enough gpt (gold/turn) to pay me the “true market value” of my techs.
The other major factors would be not to raze any cities you capture. To know more about AI attitude, read Bamspeedy’s article on AI attitude.