When I first saw this game my initial thought was that the devs were going for a psychological experience. The trailers and interviews all hinted that the people that inhabit the island are actually crazy, mentally unstable, and my guess it was some sort of supernatural force or toxin.
I have yet to play the game but it seems like the direction changed from that, Sure Vaas is kind of wako but from what I've seen he isn't loosing his mind. As for everyone else none of them give off that insanity vibe, maybe some cult-ish stuff but that it.
I was also pretty disappointed by this (Not that it was bad, but just not what I expected)
However, I'm actually more hurt about Angry Joe kind of lying to us about the drugs, well not lying but "missleading". In his review he talks about how you can mix plants to create drugs for all kind of crazy effects accompanied by cool video-footage in the background. And then in the actual game all the "cool" drug stuff is 100% scripted and the "drugs" you create are uninspired short-time buffs or healing.
Really? You didnt feel like the Dr. was insane? Or that maybe the CIA dude was also insane and didn't work for the CIA? Pretty much every main mission giving character was sketchy and you're always wondering what they are up to or if they can be trusted.