I'm jost going to limit amount of the accused.
1-As Red john appeared in season 2 final then patrick wouldn't be Red john himself.
2-When Bob Kirkland asked Jason Lonen whether he recognize him he said no, I mean why wouldn't he recognize Red John?
   Besides,  Kirkland was doing the same investigation that patrick made.Let's just imagine he's Red john;Don't you think it's ridiculous we find out who's Red john like that.
3-If you remember patrick smiled when he found broken toothpick.Just think about that why he did? He knows Red john've got plenty of rats so he would not make a same mistake twice (season 4 final).
   I certainly assume we shouldn't even beleive in the suspects list.
4-I think he's just playing games with Red john.Did you notice that during all this years as time goes by he lower his trustable friends.When I was watching 5x22 I thought he probably don't trust lisbon no more.
5-But there is something that I can't explain.How Red john killed that good memory? Maybe he has real powers!