I managed a Turn 232 victory with ten (ten!) cities. I learned a lot this game -- in particular, I learned that ten cities is probably too many. But I also made a ton of mistakes due to unfamiliarity with this type of game, so I think there's still room to explore unusually wide strategies.
My build order was Great Library into one-city National College, then three quick Settlers, then Temple of Artemis, then chill and do infrastructure for a while. I beelined Theology (got there on turn 60) and thus was able hurry Petra in an expo very quickly. Around turn 120 I spammed out five more cities, then I made one more after Industrialization.
Policies were fairly standard -- full Tradition, full Rationalism, a dip into Commerce, and Order. I normally prefer Freedom, but I felt that getting buildings up would be my biggest constraint, so I went Order for Skyscrapers. I also had tons of faith and two great production cities (thanks to Petra), so building/hurrying spaceship parts seemed easier than usual. Coal and Aluminum were no issue with ten cities worth of dirt.
Religion was Desert Folklore (despite no desert in capital), Tithe, Pagodas, Mosques, Itinerant Preachers. I needed a lot of extra happiness for all of these cities, and I figured the local culture for border expansion would also be very important for late-founded cities.
In the attached files, I have a screenshot at endgame as well as one around turn 70, so you can see my settling pattern. I placed my initial cities very far away, with the idea that I could seal off space and then backfill later. There were a couple problems with this:
1. Cities were too far away for trade routes with the capital
2. Cities were too far away to get roads up early
3. Lots of fog of war between cities = lots of barbs spawning
I think on this difficulty I should've placed my initial cities closer together. The AI is so pathetic that you don't actually have to worry about claiming spots in a timely fashion. Another thing you can see in my screenshot is that Theodora never expanded. I DOW'ed her early, stole a Worker and Settler, and then never made peace. Just keeping 1-2 units near her after this completely crippled her for the rest of the game. So I could've just prevented AI expansion using units, settled my initial cities in more normal spots, then expanded outwards later. This probably would've chopped off a ton of turns.