It's a pretty heavy shooter game but you also have to realize that concessions have to be made for the RPG crowd. The auto-aim and generally, relaxed feel of parts of the game were surely created to appease those who don't drink 14 gallons of Mountain Dew a day and can press an LT-A-B button combo while strafing in .000002 seconds.
The game isn't perfect, I'll admit that. But I can see why they eased off on the extreme shooter elements earlier in the game. Not only does it let less experienced players get into the game (some of us have to remember just how many video games each of us have played over the years) but then it allows the action to get REALLY intense near the end because they haven't used up that gameplay trick by throwing it at the player 140 times before that point.
Remember that some tricks are best used for the climax of the game and if the developer uses it too much before that point, it will become stale to the player and the intensity of the game's ending could be lost.
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