I feel like the writers dug themselves into a hole with this series. They created a villain who was at once a physical and metaphysical threat. Amon personified a revolution backed by reasonable ideology (the inherent inequality between benders and non-benders). Even if he were physically defeated, the message he preached would live on. The revolution itself would be impossible to quell without the Avatar convincing the people that there was no need for revolution through sound logic or resorting to some kind of genocide. Neither of these options are possible however because the revolution's ideology is sound in principle and because, being a children's show and a good show, genocide is uncalled for. So how can the Avatar possibly prevail? Even superman couldn't fight a popular movement of the people with all his superhuman abilities (this isn't based on evidence from a comic or anything it's just true). So how do the writers decide to handle the situation? Well, they opted for what I see as the most juvenile solution. They came up with a third option that is basically to humiliate the leader of the revolution such that he is reduced to being a villain who can be defeated with blows. Amon had to become a water bender, he had to be stripped of any legitimate claim to his ideological message in order for him to be defeated.
But the question remains: wouldn't the revolution continue? Sure the leader is gone and the second in command is presumably dead but the people must still see some truth in the original message. That their leader was a fraud might quell the first revolution at best. But there is still the problem of the inherent inequality between benders and non-benders. After discovering that his leader was a bender, the lieutenant called him a traitor implying that the cause persists despite the loss of its founding member. The cause had already transcended Amon.
This is an issue that the writers cleverly dodge by revealing Amon as a bender and this is my main criticism. The idea of the revolution is never put to rest on an ideological basis. Benders and non-benders (some of them at least) are still at war. I hope this will be resolved in the next season but I can't figure out a way for it to be. The original concept of the anti-bending revolution was brilliant and from what I've read, already existed in the fanon. It's defeating the revolution that's the hard part.