I think Red John could be someone very powerful because the only person that knows about Janes happy memories was Sophie Miller ( the person that helped Jane better) so Brett Patridge has to be Red John.

I think Red John has as his pupet that Sophie Miller. She was Jane's doctor when he was in a psychiatric ward, so maybe he told her during his therapy about those happy memories. Were I RJ, I would approach this woman, she knows a lot about Jane,plus she likes being manipulated. So no magical powers...here you go!