You'd be surprised how bad Destiny would be without the aim assist. Say goodbye to ALL of your precision kills with Handcannons and Scout rifles. The gunplay in Destiny is what makes it fun. The amount of "headshot magnetism" as I like to call it, is what makes getting precision kills so easy. Your aiming reticle slows down when you're aimed at a target, which means it's easier to get precision hits. Without that, most people would be scrubs at the game.