Ok...
You don't have to kill people. Sam Fisher however is good at killing people, why would that even be a question is hilarious. The game opens doors, action comes easier but let's not paint the picture as if this turns into Gears of War anywhere during the game because it doesn't. What happens is, if alarms go off, if you are discovered, well guess the fuck what you have a gun so you might try your odds.
You can play the game without killing, if want it much, stop being a sissy and holster your gun and sneak bitch. Knock out people without killing them, how about that?
Color changes aren't annoying, i thought the Black and white would suck, it works. What's the difference between black and white with some color thrown in when in stealth in comparison to night vision anyway?
Flashy objective signs? As in they flash? Because they don't? What you see here is what you saw in the videos.
So the controls are great, the graphics are good...and you are complaining about how you chose to play the game mostly.
The Iraq level, is a flashback sequence that changes the pace of the game, and is there for story reasons. It's a fun sequence, it's action stealth as i call it, you ain't playing with light and shadow, you are playing with the A.I. It wasn't out of place, because the game has assumed a very story driven style of pacing, and that's what it was. Just like the chase sequence. Maybe because you sucked at it? Tell me how was it any worse than those Uncharted 2 levels where you get to mix stealth with action? I know where the difference lies

7-8 hours, is waaayyy too short. Yes because you took 20 hours to finish God of War 3.
Not buying it. If you miss the old splinter cell, there's like what? 4 games out there? Go nuts.