The biggest to me was that he wasn't concerned about leaving a trail for law enforcement. Even psycho's are afraid of being caught and put in jail, this guy is just delusional -- which is why i made references to psychosis in the past. It's just strange behavior even for cold blooded killers. Which is why my theory is that drugs just totally broke something in his brain (which is NOT an excuse for the things he did: he was probably always a psycho) but lately he probably completely lost all fear and decided he can do whatever he wants and that nothing will happen, no consequences. For me that's not a "natural" state, even for "cold blooded killers". I've seen enough documentaries on real serial killers, and the vast majority of them go through meticulous steps to avoid capture (they are also usually SOBER during these crimes). I dont think this guy enjoyed killing Tim, i think he just literally didn't care and really assumed that "everything will be ok", which is kind of the delusion that some drugs offer to people -- mixed with the fact that he committed enough crimes in the past (including alledgedly murdering two seperate people) and thought he got away with it. With all of that said, OBVIOUSLY he's a freak with or without drugs.
MY TWO CENTS.