Metal Gear Rising: Revengeance has large stages for a reason. According to producer, Atsushi Inaba, they’re designed so that the player has the freedom to approach situations in multiple ways. You can choose to be stealthy, or you can face enemies head on.
You’ll also be graded when you complete missions in Metal Gear Rising. Like in other action games, the better your grade, the more points you get. These can be used to buy upgrades for Raiden. Grades go all the way up “S” rank.