Pro Allows players to create their private military company
Throughout the story of the game, the player will be trying to rebuild their private military which was lost in the epilogue of the previous title in the MGS series.
Other than building their "Mother Base" which is an ever-evolving giant structure which serves as a base of operations for the player and other NPCs which help the player, players can also recruit enemy soldiers to increase the size of their mercenary company. These soldiers can help based on their area of expertise to either work on developing new projects or be dispatched around the world to complete missions and earn in-game money.
Pro Multiple ways to approach a mission
Metal Gear Solid V gives players multiple choices on how to approach a mission or clear an outpost.
For example, the player can choose to use stealth and cunning in order to complete their mission and kill only when it's absolutely necessary, or they can get in guns blazing and kill every single enemy soldier sometimes even sniping each one of them from afar or calling the helicopter for air support.
This gives a special flavor to the gameplay and doesn't let it get stale for a long time since it leaves the choice on how to play to the player, without penalizing them for not completing a mission by using stealth (as other previous MGS used to do).
Pro Extremely intelligent AI
As the player levels up gear so will the AI, who are programmed to constantly keep the player on their toes. Being that the whole game is designed to allow the player tackle any level in a multitude of ways, seeing the AI always react differently makes for an original experience every time something is tackled.
Con Micro transactions
Something often found in free to play games is microtransactions, sadly they are included in the multiplayer aspect of The Phantom Pain going so high as $79.99 for a bundle of in game currency that can be used for advantage in the online part of the game. Considering that MGS V already is a full priced title at $59.99, to see Konami milking their fans for never ending microtransactions is pretty disheartening, especially when considering they can be used to get a leg up over others in the multiplayer by easily creating more resources over other non paying players.