I never really cared for the planning myself but Vegas ruined it for my by introducing that stupid cover system to make it like Gears of War which was popular at the time. They completely removed the ability to lean. You couldn't properly peek around a corner to take a shot without almost fully exposing yourself anymore. This meant you couldn't avoid absorbing bullets all the time. This made the game unplayable so to counterbalance that, they've added regenerating health. But then it became too easy so they kept putting you in tactically completely unfair positions against hordes of extremely aggressive enemies that can see you and shoot you through walls. They also had a lot of visually busy environments where the enemies are difficult to spot even when they're shooting at you because the sound mixing was so botched up that often you couldn't even tell when you were being shot at.

They turned it into a mindless arcade shooter where you constantly absorb bullets like it's normal and fight a whole army on your own. I wouldn't be surprised if all of this is because some Corporate dipshit forced the inclusion of that cover system because Gears of War made money.