The scheme to reinstate Lisbon to the CBI rides on the premise that Jane is so indispensable to the CBI that they would do anything to keep him on. This is problematic since we're not presented with any relevant statistics and Jane causes trouble throughout the episode. Is Jane really that much better than all the CBI agents that he can cause an inordinate amount of problems on a daily basis? In my mind the only way Jane should be kept around is if he closed twice as many cases as all other agents combined. Besides that, how can Jane be good? He skirts the law, gets other agents in trouble, and even shot someone to death.
But there was probably no way the writers could have gotten around this issue, given how they've written his character for three years. We'll just have to live with Jane and all his shenanigans and assume he'll be here to stay no matter what he does. Simon Baker has enough charisma that anything he does is charming.
Jane believes he did not kill Red John and brings back the blind woman from, I believe, the second season. She touches Carters and tells him that wasn't the man she knew, who Jane believes is the real Red John. Unless she is lying, Jane is right and has more work cut out for him.