Addictive
The pointless basecamp actually helps to draw you into the story and gives you some emotion to the game. Once your squadmates start dying you notice that the camp starts seeming a little more quieter. This is one way the game helps to draw you in. People who rush through the camp just to start their next mission will miss out on this and may very well be the reason why some people don't like the game.
The average graphics don't really hurt the game in my opinion. A lot of the same textures are reused over and over but that's nothing to really frown about. The gritty look to the game is awesome. It definatley makes it feel like you're playing back in the 60's.
Overall the game does have its faults but I guarantee if you take the time to really take all the game has to offer you will enjoy it for a while to come.