I highly doubt that any of the seven suspects on the list are red john. We've got two more seasons to go and it wouldn't be that easy to choose between seven people. There's going to be a twist and Jane will have to start over. I've got two people that I feel could possibly be red john and know James memories:

1. Alex Jane. Its been said before and the points against it are good but if Bret stiles could potentially be RJ then Alex Jane could be as well. I mean all he does is stab a few girls. You don't have to be gym junkie to be able to do that and even 60 year old men are stronger than most sleeping women. As for killing jane 's family suddenly could be because Jane slandered him and he did it to show his dominance over Jane. After all he did bully Jane and with Jane going to the carter springs place and the Irish guy saying his dad was wicked comparing Jane to him it seems like huge hint. Plus we haven't seen his actual appearance outside of the flashback and with all these hints were bound to see him unless he's dead.

2. This is a far shot but it could be the owner of the mental hospital Jane was in. He could easily drug Jane and hypnotize him finding out his thoughts, ambitions and memories plus all the accomplices are screwed up so he could "cure" them and turn them into accomplices via brainwashing. Sort of like visualize but with paranoid schizophrenics and deeply tortured souls. Makes perfect sense. His web of followers could branch out from this because even normal people have mental breakdowns especially if red john is the one causing that breakdown and pain in order to get them to go to the mental hospital so he can work with them and make them do his dirty work all in the name of liberation and his grand scheme Rebecca was talking about.Could also be a part time psychologist. Plus this would give him tons of money, skills, willing subordinates, and most importantly motive. He wants an army of cdazies to take over the world, show them his pain and then guide them down a " higher path."