Wall of Migs, now that's a classic. It was much much more evil back in the SP1-4 days, makes the present worst case scenarios look almost enjoyable
To be honest the dynamic campaign in this one is next to none, and something from which from example the Silent Hunter-series could take note. More often than not even a small impression on that your actions might have an effect on the end result is much more interesting than being dropped in the middle of a "war on rails" a-la SHs, and generally most other games.