I settled on the southern of the two silks. The thinking was to settle closer to the centre of the map and block more land, while accepting that I'd lose a floodplain and potentially a river tile or two in the late game. I then teched BW while building a warrior until I reached size two. At size two I switched to a worker and then, when BW was in, switched to slavery and whipped the worker.
I then went agriculture, AH, hunting, archery, fishing, pottery, writing.
Until AH was in, I built one riverside mine and worked that and a floodplain at size two while chopping everything. There wasn't anything decent to grow on to so this felt OK, albeit it was a bit strange to not really be improving tiles or growing the capital. Chopping just seemed a lot better than spending 7 turns farming a floodplain and, the big downside of the settling on the southern silk, was that I only had one hill to mine anyway. I think I even one pop whipped a second worker taking the capital down to size 1.
The idea of blocking land - which I maintain was valid - also turned out to be of zero value given that city two went directly south to claim the corn and fish. It also meant that there was a small gap between my capital and city three - the crab and wheat spot - even after that had popped borders once and the capital twice. It didn't end up mattering but Joao is not who you want on your borders when there are gaps to exploit.
Settled my fourth city turn 64 and got writing the next turn. At this stage I had four workers and was just about to finish a granary in Djenne but had no other infrastructure.
Hard to compare with going AH first, but judging from
@CarpoolKaraoke's screenshot from T60, it's comparable. I think my tech might be slightly ahead and Djenne better developed but the capital in worse shape and I've no forests left. I'm playing faux deity but I'm not sure that makes much difference in terms of player expansion; it's just that the AI only starts with one settler.
I've met Isabelle, Joao and Wang but not Sully. I shouldn't have read other people's T60 write ups because this made it clear that it was a pangaea.