Patrick Jane's father could be Red John. Patrick left his father tired of cons. No-one knows his(father's) life after that. But Patrick appeared on TV with physic cone and commented about Red John. Again, Red John plays with Patrick and wanted to be a friend and associate. His father always believed together they made a good team).Not that he wanted to hurt him. In 5th season Red John kills someone(girl) who was a good memory for Patrick from his childhood and brought him back to his hometown.
Who else other than his father could know a secret childhood memory.
Also the girl who died lived with his uncle who was a partner of Patrick's father.

I also strongly believe there is a helping hand inside CBI for RJ.
Could not be one of the seven suspects because RJ would not have spared them since he knows PJ is suspecting them.