It has already been mentioned but Dues Ex: Invisible War.
Now to be fair I know NOTHING about great game design. The reason I picked Dues Ex is that it was the first game to let me do Exactly what I wanted to. I feel it's given me the most freedom and range of choice as a player and does so while losing me in it's story. One of the most amazing and rewarding games I've ever played.
It's even the first game that ALMOST made good on it's promise that I could play it through with nothing but stealth and a tranq gun. I was soooooo close, but there was no way (that I found) to tranq the mechs.
Now to be fair I know NOTHING about great game design. The reason I picked Dues Ex is that it was the first game to let me do Exactly what I wanted to. I feel it's given me the most freedom and range of choice as a player and does so while losing me in it's story. One of the most amazing and rewarding games I've ever played.
It's even the first game that ALMOST made good on it's promise that I could play it through with nothing but stealth and a tranq gun. I was soooooo close, but there was no way (that I found) to tranq the mechs.