The Kyoto protocol was an excellent piece of environmental legislation, and its sucessor should follow a similar pattern. The biggest weakness of Kyoto was not the protocol itself, but the fact that important nations (like the USA) did not sign on and give it their full support. If the sucessor to Kyoto can keep its rigidity while also gaining the support of every industrialized nation, it will absolutely benefit the world.
The kyoto protocol admittedly does need some revision but should not be thrown out entirely. It is not a perfect system but it does its job well. With that being said its replacement doesn't need to be a completely new system, that will be harder for those who already use it to learn, it should be something based off the Kyoto protocol but has the necessary improvements.