@101mrniceguy10101, the mod Wars of Liberty is legendary bad for treaty. I'm surprised how you didn't know about that. I'd recommend you to play treaty with The Asian Dynasties only.
Also, the creator of Age of Empires III did not make AI able to play on treaty mode (eh, another proof that treaty is not really appreciated), and my knowledge is a little limited for the moment to fix that.
But, if you insist, I'd recommend you to use the Zen Master AI, coded by Panmaster. It's exclusively made for playing on treaty mode (but it's a Work in Progress, thus some bugs may occur). You might even want to modify it so that it can play with Wars of Liberty (for the moment it is for The Asian Dynasties only).
Anyway, feel free to suggest anything to make them even harder (if possible, give suggestions about Supremacy).
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