Agree with all of this although my favorite has to be the sk tribute one. They are all good.
I remember the one where Jules went undercover in the sorority. Her pink binder was a character unto itself. The secret to Psych is that at first it seems like a bunch of normal people dealing with Roday's "out there" fake psychic guy. Then you realize that they're all crazy in their own ways and that Shawn is, in many ways, the most stable overall.