I'd first like to point out several series inconsistencies revolving around each of the suspects, inconsistencies that imply the suspects are not Red John because they imply something else.
Bret Stiles is nearly usurped by Jason Cooper in Visualize, yet the next time we see Jason Cooper, he's still on Visualize's Board of Elders. His explanation that Bret Stiles is a very forgiving person. What? No, he's not. All the evidence we've seen of him suggests that, while highly intellectual, mercy is not in his vocabulary. Two pertinent points regarding Visualize stick out to me. Red John was either a member as a late teenager or he hung around members. Bret Stiles has intimate connections with Red John. If he doesn't know who Red John is, he knows how to get in touch with him. Finally, Jason Cooper is going to be in the episode where all the Red John suspects are gathered together by Jane, which implies the scene is going to be held at Visualize.
Is it not likely that Jason Cooper, around the same age as Bret Stiles and in a position of authority that is nearly equal to Stiles, knows who Red John is as well? Before the list of 7 came out, I would have put Cooper on the list. Now, I think that he's fully aware of Red John's identity. However, there's NO CHANCE he'd try to take over Visualize if Bret is Red John. Absolutely none. If Red John is leading Visualize, nobody that knows this is going to try to stage a coup. I believe that this sufficiently rules out Bret Stiles as a suspect.
Kirkland time. Besides the overwhelming evidence that he's going to die tomorrow night, there's the simple matter that Loralei made the video and died three episodes before Kirkland had men brake into Jane's room. Meaning that Red John didn't get his information from Kirkland. Kirkland has no connection to Red John as an accomplice, associate, or acquaintance. As many other theorists have concluded, he's searching for Red John as well. Why? That's anybody's guess, but given the way he kills Jason Lennon, I would hazard a guess it's because Kirkland had a personal relationship to Loralei's twin and he also deduced that Red John killed her, motivating him for revenge just as Jane is motivated. Kirkland is gone too, probably quite permanently in about 24 hours.
Brett Partridge. I have to include this paragraph because of all the theories that he's still alive. I believe they are supported by the lack of any on-screen evidence following his murder. If the show's producer's didn't want us wondering about his life or lackthereof, they'd include some sort of a shot of his dead body at the beginning of the second episode. He would also never quote The Tiger if he was uninvolved with Red John, and given all the previous evidence supporting him as Red John, it's unlikely he'd be a Red John accomplice and more likely he'd be Red John himself. It could also be possible that he is dead and that he orchestrated his own murder to deny Patrick the pleasure of killing him. This conclusion is supported by the 'big clue' at the end of the first episode of season 6, which is the wrong eyes on Lisbon's makeup. Red John wouldn't screw that up. Somebody who is ordered to kill him, somebody who has never drawn the face before, would. That's my theory, as far fetched as it may be, and to all those who point to the list of actors in the Red John reveal episode, the cast list in other television shows has been disguised to keep a plot point hidden, and there are no legal requirements that all participants of a television series have their names credited.
Assuming that this isn't the case, however, since that's the current bandwagon we seem to be jumping on, Partridge, Stiles, and Kirkland are out. Haffner, McAllister, Reede, and Bertram are still possible.
Three of these characters are meeting in Bertram's office in 6.02, when Patrick enters specifically in order to frighten Red John into action. Patrick believes one or more of them are Red John or his accomplices, or he would not have bothered. We know that Reede expects Bertam to be aware of Jane's progress on the Red John case, we know that McAllister has been following Jane around (watch 6.02 more carefully if you don't believe that) and none of them seem to worry about speaking plainly in front of each other. Either Red John is in that room, surrounded by accomplices, or all three suspects are accomplices.
Of the 7 suspects, Reede Smith is the only one in the FBI. If 6.01 focuses on Patridge, 6.02 focuses on Haffner, and 6.03 focuses on McAllister, given the pictures and trailer for this week's episode, 6.04 is going to focus on Reede Smith. We know that Patrick's plan at the end of Season 5 didn't work because Red John had an accomplice in the FBI. It's likely that person is Reede. Originally, I had hoped that Reede would die by Kirkland's hand in 6.04, eliminating both of them as suspects, and leaving Haffner, Bertram, and McAllister to vie for RJ. While that doesn't seem likely anymore, Reede Smith comes across, in the conference scene with McAllister and Bertram, to be a middle man at most, and if we go by that analysis, Bertram is a middle man at most as well, as he appears to take orders from Reede. If Red John were working for the FBI or operating with their knowledge and consent, this makes sense. Otherwise, Reede is the least likely of the four and Bertram the 2nd least likely WITH ONE POSSIBLE CAVEAT:
Looking back at the finale of Season 3, the assassin enters Bertram's room and scales down to Craig's room. Let's assume that Bertram is Red John and Craig is an accomplice. They would get conflicting locations on Hightower's actual room number, solve the issue by having the assassin check both. Otherwise, the assassin would just enter into the correct room. There's no need for subterfuge. Grace then tells Craig that Bertram is the mole and that's she's going to see Hightower, he tags along and lets Bertram/Red John know that he's going to kill Hightower. Bertram/Red John is at the food court, decides to leave and....passes on the cell phone to Timothy Carter, possibly an undercover bodyguard keeping an eye on Red John. Possible theory, not my main point, but if this happened then Bertram is no less valuable of a suspect than McAllister or Haffner. Moving right along...
McAllister is one of the few suspects who appears genuinely good-willed, and yet he is undeniably involved with something at the least, and Red John at the most, and he's keeping an eye on Patrick. That last fact implies that he's keeping tabs on Patrick FOR somebody else, not because he's Red John.
Haffner is my favorite suspect, unless Patridge is alive or the above mall scenario with Bertram actually went down. The best thing I can say about him is that there's nothing that seems to contradict him as a suspect. He actually fits the description we get of Jay Roth best, out of all the suspects. You can fake being a sucky whistler, but you can't fake being a good whistler. His demeanor is of somebody with many friends...he's certainly a likable guy most of the time, whereas Bertram or Partridge or Reede Smith can give off other vibes. He's well-spoken and good postured, and a patient person as evidenced by when Lisbon keeps postponing their lunch and he isn't flustered at all. He appears to deal well with conflict and adversity, but in actuality does not. Well, we don't know if he really doesn't, but Stiles, Reede, Kirkland, and Bertram all have scenes where they appear to momentarily lose control of their emotions, even if those scenes are brief and nondescript.
Cliff Notes:
Not Kirkland, Reede, Stiles
Probably not McAllister, or Bertram
Maybe Haffner
Hopefully Partridge.
I think it would be the best possible solution for Partridge to be Red John, and with so many people saying, "I think it was supposed to be Partridge, but the fans discovered it was going to be him so the writers changed it", I'm surprised more people aren't supporting Partridge by calling a double bluff on the part of the writers, pretending to kill Red John off or actually killing him off in order to produce the maximum thrill.
We're getting close! It's only a month from last Thursday away.