Okay, so just to be clear, I'm not complaining about who Red John turned out to be. I truly think the whole McAllister as RJ thing could have been a great story. Really, Patrick Jane beating McAllister at rock-paper-scissors when they first met provided some brilliantly subtle yet potent and chilling (in hindsight) foreshadowing. Surprisingly, Xander Berkeley did a pretty good job coming off as deranged and creepy but still intelligent enough to pull off what Red John has pulled off. There was so much there to work with. Unfortunately, the end of the story was so rushed and so poorly told. That's what left me feeling so disappointed.  

It only makes sense that if you spend five seasons setting up your story -- leaving cryptic little clues, giving your audience background information, slowly adding pieces to the Red John puzzle -- you need to spend enough time on adequately finishing that story. You need to connect all those clues to McAllister's history and spend more than ten minutes doing so. You need to show your audience how perfectly all those pieces fit together. You need to commit to and sell the story you settled on and make your audience believe that it really was McAllister all along. 

I personally think it would have been cool to spend this season showing the most important parts of the story from McAllister/RJ's point of view. Flash back to what happened at the barn. Show me how McAllister came to be connected to Visualize, and while you're at it, tell me exactly what Bret Stiles knew about the whole thing and how he knew it. Devote time to showing me more about McAllister's interactions with Orville Tanner, Rosalind Harker, Michael Kirkland, Timothy Carter, Lorelei and Miranda Martins, etc. Explain the significance of the "Roy Tagliaferro" alias. Show me McAllister's therapy session(s) with Sophie Miller. Tell me exactly what chain of events led to the creation of the Blake Association. Don't just tell me that McAllister is Red John, show me how and why McAllister is Red John.

I honestly think this could have been a great story, but the execution was just plain sloppy. Great job setting it up... but the ending (the last eight episodes) was so, so poorly done. It's a shame.