Here's what I think would be neat.
Remember how when Aang fought Ozai there was that danger that he could have the technique rebound back on him if Ozai's spirit was too strong? Well, what if, before the final battle, Korra undergoes some serious spiritual training and has some kind of epiphany. Then she fights Amon and loses. But when he tries to take her bending away she overwhelms his spirit and takes away HIS ability to energy bend. Then, while everyone is stunned, she breaks away and takes them all down single-handed.
Also, Lin should take over Sokka's role as the non-bender who is a good enough fighter to contribute to a bending fight. I want to see her get really pissed off and tear some chi-blockers apart with her bare hands.
"Oh no – you blocked my energy flow with your pressure-point attacks. What will I ever do now – LIN SMASH!"