How many cities do we want?

Title says it all (I'm getting good at this ).

Should we build more settlers and found more cities?

I think yes. We should first ICS the corrupt region (can still fit in a few, I think), and then start filling up the core as well. I see it this way: we don't really need the production power of the core region, but we do need more culture per turn. We still can build a few libs and temples, but most of our cities have these improvements by now. The core region generally has universities and quite a few cathedrals as well. This means that the best way to generate more culture is to build more cities, and give them libraries and temples.

We are currently doing some 500 cpt, and at that speed we have another 200 turns or so to go. That's two or three more terms. I would like to speed this up as much as possible. I had hoped we could end by the end of next term, which is probably no longer possible, but I still think we should try to finish a lot quicker than in 200 turns.

More, yes, but keep the high production part of our core free until right at the very end as destroying that will destroy our ability to produce units for rushing.

More yes, More and more and more as long as we dont dominate.

Currently have 129 cities:

• 15 of these have at least a library, temple, university, and cathedral.
• 24 have at least a library, temple, and a university or cathedral (or are in the process of building the uni or cathedral, and should have it built in a reasonable time: by the end of the month).
• 46 have both a library and temple (or will have the second one built by the end of the month).
• 26 have just a library or temple (or will have one or the other built by the end of the month).
• 18 are building their first library or temple, and are building so slowly that they won't have completed it by the end of the month.

We start the next turnchat with 21,321 culture points and are accumulating 552 culture/turn. Nice, but pretty pedestrian. By the end of the month we should be accumulating over 700 cultural points per turn. Better; at least this puts us on a pace to finish sometime in August.

Clearly we have enough cities right now to win. However, if we ramp up our culture to at least 1000/turn we'll win that much faster. How do we do that?

The easiest way is if we stop building additional unis and cathedrals except for those that are already well into production. NaN4 is building a cathedral that won't be done for another 160 turns; better to put that city on wealth, which will give us another GPT. (And we shouldn't even think about coliseums; they cost twice as much as a temple and have twice the maintenance and yield the same 2 cultural points/turn.) The marginal cost of additional unis and cathedrals isn't worth it (except in very productive towns, and we’ve built the 4 major cultural improvements in virtually all productive cities). Rather I'd rush libraries and temples in all existing cities that don't have them, then I'd build new cities and rush libraries and temples in them. We'll rush with both gold and by building military units in our productive cities and disbanding them in our corrupt ones. (BTW, in this post SirPleb has an excellent analysis of how to go about building culture in corrupt towns with the goal of achieving an early culture win.)

Long answer to the question, how many more cities should we build? And I haven't even answered it yet! 200 cities has long been our goal for the most efficient (fastest) win; if we had that right now, we'd be talking about winning the game a month sooner (which has the downside of ending our pleasure with DG6 more quickly). It may not make sense to build that many now, because building that many cities may outstrip our abilities to rush culture in new cities in a timely manner. I would guess that if we build about another 30 cities that we'll be able to comfortably handle rushing libraries and temples in each by the end of the game. (Although I certainly invite someone with the time to do a proper analysis to come up with a better figure than my guess!)