Complexity to you could mean solving a Rubics Cube, while getting pummeled in the back of the head by Mike Tyson AND chewing ten pieces of bubble gum. While chewing this gum you must blow a bubble every ten seconds or else Mike Tyson lops your head off. Did I mention you must do all of this with your eye closed? Now this is just an example, and in no way am I trying to guess what you do on your spare time.
Wow, that does seem to be complex, haha! It's not necessarily the result of failure that makes it complex, though. That just adds to the emotion. But having to do all of those things at once... that's what makes it complex! Not to say complexity is always a good thing, but that is complex.
Does a lack of a dialog choice preclude me from doing what my character would want to do anyway? Perhaps the issue here is that it is too open ended in that you write your own script through your actions and not by clicking on a conversation choice.
I suppose lack of dialogue choice makes it break immersion and depth. What I would say causes much more grief is the inability to choose to kill a random, or even non-random, NPC because they are classified as essential. It's quite silly, really. I tried to intervene in the beheading scene in Solitude just to see what would happen. I managed to kill ALL of the guards and many townsfolk. But this random argonian (I believe) simply would not die. He kept getting back up, but still came looking for me after I ran away and hid. I knocked him out numerous times, but there was no escaping his wrath.
Not to mention that the same system really limits you from truly role-playing an assassin-type of character. Why can't we kill a random jarl or queen or general? I can kill all their guards, but not the actual leaders... or even a simple shopkeeper sometimes. That's the exact reason I got turned off of Assassin's Creed. I went to great lengths to position myself strategically for the first main target, especially after being preached to about stealth. Then when I finally get close, the screen flashes, my character sheathes his weapons, and all I can do is casually walk. I was forced to walk closer and closer to the target until a cutscene began. So there I was, having prepared for a rooftop ambush, now finally regaining full control of my character five feet in front of a row of hostile guards who were already charging me. It turned into a full-on melee, not a stealthy assassination. It's needless to say that I have never played another Assassin's Creed game.
Ps. Thank you all for giving your thoughts!