Assumptions:

Each city is built on a square that yields 2 food, 1 shield, 1 trade. Each city has a choice of three types of surrounding terrain to work:
1 food, 2 shield, no trade (forest)
2 food, 1 shield, 1 trade (grassland)
1 food, no shield, 2 trade (ocean)

Each city must build a warrior to keep order, then will build settlers. It takes 10 turns from
the time a settler is built until it can build a new city.

When a city builds a settler, its size decreases by one and any food in the box is applied at
that new city size. So if a size 2 city with 20 food in the box builds a settler, it stays at size 2. I think this is how the game works, but haven't done a detailed study.

Cases:

Player A puts all his workers on ocean. He builds a warrior in 10 turns, and a settler 40 turns after that. 40 turns for each subsequent settler. It takes him 20 turns to grow to size 2. His cities generates 3 trade/turn while size 1, and 5 trade/turn while size 2.

After 50 turns: 1 city, 1 settler, 210 total arrows
After 100 turns: 2 cities, 3/4 settler, 560 total arrows
After 150 turns: 5 cities, 2 settler, (2) 1/2 settler, 1310 total arrows

Player B puts his worker for size 1 cities on grassland, then moves both workers to ocean after his city grows to size 2. He builds a warrior in 5 turns, and a settler 35 turns after that. It takes him 10 turns to grow to size 2. 35 turns for each subsequent settler. His cities generate 2 trade/turn while size 1, and 5 trade/turn while size 2.

After 50 turns: 2 cities, 190 total arrows
After 100 turns: 4 cities, 3/4 settler, (2) 3/8 settler, 635 total arrows
After 150 turns: 8 cities, (3) 3/4 settler, (3) 3/8 settler, 1/4 settler, 1660 total arrows

Player C puts his first worker on grassland, and his second on ocean. He builds a warrior in 5 turns, and a settler 20 turns after that. 20 turns for each subsequent settler. It takes him 10 turns to grow to size 2, but his cities never drop below size 2 after once growing there (20 extra food generated while building settler, just enough to stay at size 2). His cities generate 2 trade/turn while size 1, and 4 trade/turn while size 2.

After 50 turns: 2 cities, 1 settler, 200 total arrows
After 100 turns: 8 cities, (5) 1/2 settler, 860 total arrows
After 150 turns: 21 cities, 13 settler, 3060 total arrows

Player D puts his worker for size 1 cities on grassland, then moves one worker to ocean and one to forest after his city grows to size 2. He builds a warrior in 5 turns, and a settler 15 turns after that. 17 turns for each subsequent settler. It takes him 10 turns to grow to size 2. His cities generate 2 trade/turn while size 1, and 3 trade/turn while size 2.

After 50 turns: 3 cities, 1 settler, 29/40 settler, 186 total arrows
After 100 turns: 14 cities, 1 settler, 7 partial settler, 945 total arrows
After 150 turns: 47 cities, 10 settler, 24 partial settler, 4178 total arrows

Player E puts his worker for size 1 cities on grassland, then moves both workers to forest after his city grows to size 2. He builds a warrior in 5 turns, and a settler 11 turns after that. 14 turns for each subsequent settler. It takes him 10 turns to grow to size 2. His cities generate 2 trade/turn while size 1, and 1 trade/turn while size 2.

In the early growth phase, grow your city to population 2 as quickly as possible. Then place your citizens to maximize your shields.

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Old posters never die, they just f.a.d.e..a..w..a..y . . .

The premise of a settler averaging 10 turns before founding a new city would require at least laying down some roads once you get past say, 20-25 cities. Otherwise, how will you get settlers from your core cities to unsettled land with the resources you outline fast enough to meet the 10 turn average? Anyway, certainly some food for thought in there.

I agree that the ICS does take some of the challenge out of the game. An ICSer has fewer decisions to make, therefore has an easier game. On the other hand, I think most experienced players have their games pretty well scripted. You're not going to stop in the middle of every game and ask yourself "Hmm, should I build a library or marketplace first?". You've decided what works best for you, and that's what you do.

ICS is not some sort of dastardly cheat that robs the game of its challenge and fun; rather, it's just the most efficient way to play. Look at a couple of the popular Windows games: Freecell and Minesweeper. The former is winnable every game; the latter, most games. Yet people still play those games and don't impose handicaps on their gameplay to make the game more challenging. The object is to have fun, nothing more nor less.

Imagine if the AI had been taught the ICS technique. With its happiness and production cheats, the AI might actually be a challenge!

Thanks, DaveV. I will try it one of these days. It has to be a faster paced game than my usual ones, I suppose.