Eurociv, Granaries are a waste! I never build those. Well, they are the VERY LAST thing my cities build after SDI and SAM and whatever else. Same with barracks until later in the game.
What I am typing here is essentially another's strategy with a little tweaking and it works well. This works well for Chieftain to Prince, maybe higher too, but I play Prince. 5 - 7 cities is enough for me usually. Obviously, a small island is great for this, helps to avoid early war and theft.
So, build 1st city, build settler. Build second city and have both do another settler. Keep goin until you have 5-7 cities and then have each city build a settler for land improvements. Don't necessarily NEED one settler per city for working... (recently did 5 cities with 3 settlers/engineers) once you have your core of cities and a settler to work the land, build a temple. Then Wonders. I do Hanging Gardens, Colossus for SSC, Great Library IF you desire, or whatever else you want. All cities get temples, 2 or 3 cities build wonders. Obviously, tech research goes normally, go for Monarchy quick, then Currency and Trade. After temples, non wonder builders do marketplaces. After wonders, marketplaces. Then caravans every which way you can to set up trade routes. Obviously, with the SSC, I build a library rather than marketplace, the marketplace will come later. Get Republic and drop science to zero and put lux and tax at 50 each. We Love The Leader Day!!! Even if you need to put Lux up to 80% to keep the cities growing each turm, do it, you still turn a profit with the taxes and trade routes. Max each city to 8 and continue with caravans and city improvements. (At some point, build a defensive unit for each city) Partial rush buy aqueducts when possible, and max each city to 12. Keep lux at 10 or 20% to keep people happy and up the science again. Coloseums are necessary before long. Lower lux when each city has one. Harbors are good for food production. Caravans keep going when you can. (Thanks to Starlifter for the caravan enthusiasm...) So in general, temple, marketplace, caravan, improvement, caravan, improvement etc. until no more caravans are buildable... Max out population of cities meanwhile. Building necessary wonders (what you deem necessary) can distract some of the caravans from setting up trade routes but do what you can. Once each city has temples and coloseums, do sewer systems when you get sanitation. Partial rush buy them also and crank the lux again. Get Cathedrals going in each city or if you prefer Michelangelo's... I go for space race lately so with only a handful of cities, it makes more sense to just build them singly. I always go for Leo's to keep it from other civs and to upgrade my few defensive units automatically along with settlers to engineers. And of course, Democracy quickly is also a good thing. Helps out with tech. So soon enough, you have 5-7 cities with a population point of hopefully 21 or more each, convert extra citizens to scientists, lux at 10 %, 20% if necessary, no more military units than the number of cities you have, close to one engineer per city, and STILL alternating between building caravans and city improvements.
Obviously, this works best if you get to start on a smaller island with no rivals sharing it with you. Skip battles and hassles, just get to building a great, albeit small civ. Your tech will be number one and space is not too far off.
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