There are games that you're playing, and at some point you're thinking: "Damn, I wish this thing would end already".
This means that the game svcked, because if you're bored and feel like you've done everything important, enough times, and the game still goes on... the SP was bad. Atleast for you.
This was how Crysis 2 was for me.
Then there's the "Aww yeah" right at the end followed by a "Aww man! Why'd it have to be over already?!"
This means the game was good, and worth buying and playing.
This was how for instance, Red Alert 2 was for me.
There's still, the ultimate game that will make you go "HOLY CRAP, THAT WAS AWESOME" at the end, thinking back on all the good, the scary, the tough parts. It will make you think of how you were lurking somewhere in the beginning, assessing the situation and then doing what you wanted to do in order to make things right. This has been a perfect game, for you.
This is what Crysis 1 was for me.
So how did it come to this? From a game that was simply breathtaking, exciting, beautiful etc. to a linear singleplayer that you only played because, I mean come on you bought the game.. you should atleast play it once through.
In Crysis 1, there seemed to be several different ''mini crysises'' that were all better than the entire C2 singleplayer. The inside of the alien ship was one. When you got to drive tanks across the field was also completely different. Sometimes you busted up the place with guns, sometimes you snuck in and threw DUMPSTERS at your foes with strength mode. You'd be amazed by the epicness of the crumbling mountain far across the distance, thinking: " Holy ****, ALIENS, we're SCREWED, AWESOME". And later on, boom, everything is ice, and later again, you're on a CARRIER. Sneaky, VTOL, tank, alienship, carrier, jungle, town, bridge.. so many different aspects.
So much with Crysis 1 singleplayer is so god damned epic. So why isn't C2 SP epic?
Because it isn't really anything. Compared to C1, the suit is dumbed down, your options are dumbed down a LOT. The story is VERY dumbed down, and to make matters worse, it's changed. FOR THE WORSE.
No more being overwhelmed by blue shiny flying aliens, gunning them down because you got caught. Just a bunch of weird red aliens that were visually impressive, in the trailer.
Most of the C2 singleplayer was all the same. Go there, kill stuff on the way. Collect stuff for your suit, oh look, more aliens. The ''tank'' alien, the pinger, was a complete waste of time. It was ANNOYING to fight it, not hard. The exosuits in C1 however... damn, that was something!
So. Before this turns into a novel, for anydev reading this. For your humanitys sake, don't screw C3 up like you did C2. It was horrible, the MP too. Why am I still playing it? Because it's barely more amusing than BF3.
tl;dr: READ IT