I know a lot of people had problems with invisibility in Crysis - it made things too easy, whatever - but I liked it. But then again I'm pretty much of a coward player. Still, it would have been nice if they introduced certain elements that could see through your invisibility: sensors like in StarCraft, enemy nanosuits with goggles or something. That would make true stealth an important part of the game, at least at selected moments. Plus it would keep cowards like me on our toes.