Here are the Pros and Cons of the different Ancient Wonders. Included is a list from 1-7 in descending order of helpfulness.
The Great Wall:
“Based on the Great Wall of China, this series of earthen and stone fortifications provides great defensive benefits.
Benefits: Gives your capital a 50% defensive bonus.”
Pros: This sounds like a pretty good wonder. It protects your capital from 50% of all harm. It could really save your city during an attack.
Cons: It only protects your capital. I suspect that empires will become very large throughout the game. Your capital might be safe, but only your capital.
From the guide: “This classical centre of learning provides a significant bonus to research (though it does not unlock any new research options).
Benefits: Acts as a level 5 Library in your capital.”
Pros: A level 5 Library can help out a lot with research times.
Cons: Today is my second day after getting classic, and before this day is over, I’ll have a level 5 library. Don’t buy the hype. This wonder’s not worth much.
From the guide: “This Indonesian candi-style temple has a calming effect on all around.
Benefits: Reduces the frequency of Barbarian attacks.”
Pros: Barbarian attacks can be quite the hassle. Preventing them may help a lot in the long run. Since it doesn’t specify the capital, I assume it protects ALL of your cities.
Cons: I don’t know haw strong barbarian attacks will be later, so thins may or may not prove to be useful.
From the guide: “The Roman centre of sport and spectacle, this amphitheatre improves the morale and work ethic of your population.
Benefits: Produces 1000 of a random resource daily in the capital.”
Pros: It’s free resources!
Cons: I make 6x this much of every resource (save iron) every day. I make 10x this much wood every day. This isn’t worth a dime.
The Great Aqueduct:
From the guide: “Based on the Valens Aqueduct in modern-day Istanbul, the Great Aqueduct draws more water into your capitol to aid growth and sustain a healthier population.
Benefits: Adds 25% more population to your capital.”
Pros: More people = more gold. Gold is necessary for research and military, so this should help out a lot.
Cons: Military eat up money fast, so I’m not sure how much good this will do you if you want a large military.
From the guide: “This magnificent, gilded pagoda acts as a source of inspiration to the architects of your empire.
Benefits: Provides an extra construction slot.”
Pros: This is great. An extra construction slot means much faster building. I love it.
Cons: It wasn’t here when I left ancient…
From the guide: “Based on the site of Apollo’s battle with the serpent Python, this wonder inspires your empire’s youth to do battle against the serpents of today.
Benefits: Boosts infantry training speed by 30%.”
Pros: If you want a military-driven empire, or you just want good defense for all your cities, this is a great option. It’s what I chose.
Cons: So far, there is no PvP. Until we can attack each other, this is almost useless.
List from useful to useless:
1. Shwedegon Pagoda
2. The Great Aqueduct
4. The Great Wall
5. Borobudur Temple
6. The Colosseum
7. Plato’s Academy