This aspect of the game is neither funny nor fair.
Despiting the AI on higher levels is " forced " to cheat , knowing in advance which UU a civ have cut a bit of atmosphere IMO.
If you pick up Rome for example you know that the best moment to have a war is across the Legionary unit, while if you pickup Americans you'd better wait for B52 etc... otherwise it would waste your unique unit advantages. Meanwhile not only you know when the story will " praise " you but you also know when the story won't praise a known opponent......
I call this " The Nostradamus Bonus " .
Doing that it is like knowing a bit of future since 4000 b.c. and that's not fair neither funny IMO.
I would have done something like this instead :
The unique units is been spit out just like great men, quite randomly and once only during a game for each civ. Adding few characteristics to an existent unit or possibilities to customize it a bit, just like in Alpha Centauri.
This way the plot couldn't be written in advance......
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