I posted this in comment section, but obviously it should be here as a theory.
Also, we need Marcus Pike on the suspected list.

I dismissed Marcus because it was too obvious. Mainly for his name matching the "he is Mar" but in retrospect and in acceptance that Partridge might not be Red John, Marcus seems like an adequate replacement. Heller hid him in plain sight. He certainly knows his way around woman, a necessity from my point of detecting, and has the resources to pull of anything Red John was associated with.

Bruno said Red John is on the list, and he was (McAli). From the creators perspective, if you want to conceal the real Red John, but you were asked that question the only practical answer would be the one he gave. I'm sure in his place YOU would not say: "Yeah, I'll have a fake Red John and he is on the list but the real one is yet to come". YOU would not say that if you want to keep the suspense going. In this case he didn't lie just didn't say the whole truth. Also supports the theory Red John is too smart to be on the list to begin with.

Jane shook the hands of Red John. If you know Lorelei's original slip of the tongue, you know she put no time frame to it. Red John could have met, scratch that I'm sure he met Jane before he killed his Family. Perhaps Jane's Father with Jane's assistance embarrassed Marcus in their carnie past? Perhaps not, but ever since Jane started compiling the list, the whole thing felt wrong to me. Placing something important in the memory box is not unheard of, but hand shakes: Come ON. They aren't that important, therefore overlook can happen.

Marcus' promotion was surprise too. Perhaps Jane was getting too close for comfort. Also, Jane showing interest in other departments case was strange even to those close to him.

Jane is also concerned about Marcus when he ask Lisbon about her dumping him. Why does he do that? It could be interpreted two-fold. 

I was hard pressed on Partridge being Red John, but Marcus seems more and more qualified for the position. We might see Lisbon's hands stretched from two directions and the rivalry for her affection might have much deeper roots.

No suspect chosen for this post, but Marcus would be the one if it was possible.