It's so boring that unique units/buildings are necessarily bonuses (boni?) 
Let's come up with a list of unique units/buildings that confer negative effects instead
Strategy will then have to take the negative aspects of your civ into account as well

French
Unique wonder: Maginot Line (replaces Great wall)
It looks just like the great wall on the map, but has big holes in it through which your enemies can invade.
Indians
Unique unit: Slow Worker (replaces Worker)
If anyone's been to India, he or she would know that workers there never finish projects on time, like to strike a lot, come in to work late, take 2 hour lunch breaks, etc.
Americans
Unique building: McDonald's (replaces Grocer)
Instead of a health bonus, you get a health penalty
Others?

Let's come up with a list of unique units/buildings that confer negative effects instead



French
Unique wonder: Maginot Line (replaces Great wall)
It looks just like the great wall on the map, but has big holes in it through which your enemies can invade.
Indians
Unique unit: Slow Worker (replaces Worker)
If anyone's been to India, he or she would know that workers there never finish projects on time, like to strike a lot, come in to work late, take 2 hour lunch breaks, etc.
Americans
Unique building: McDonald's (replaces Grocer)
Instead of a health bonus, you get a health penalty

Others?
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