It is also true that aspects of Aiel culture are very attractive to many people in the Wetlands. While the Aiel may frown on the distorted Ji'e'toh they see in Cairhein, they also seem extremely willing to inculcate outsiders to their way of life if asked.

The Shaido in Malden are not a real indication of how the Aiel would behave in a conquered land because they set out to loot and pillage. They had committed the ultimate crime of rejecting the Car'a'carn, so what does anything else matter?

I think Aiel success would have meant an impractical attempt to impose ji'e'toh as a way of life in the Wetlands, which may well have ended with the system organically mutating itself to something that makes sense in the Wetlands, but also allows for coexistence with the Aiel.

Of course, the easy solution is to demand the impossible from the Aiel. Ask them to give up all weapons, and give up being warriors, to sing songs to make the world better. They'll see that there is insane amounts of ji in doing that, and apply themselves fanatically to being a peaceful people.