I don't have civ installed on this computer, but I checked the save with crprings and this is what I'm seeing: a fairly strong position at RCP5 and as opposed to RCP4. On the other hand, I think an argument can still be made for RCP4 because squeezing more cities into the map means more opportunites to build culture.
Counting Schizobane, we can get a total of 8 cities built at RCP5, 6 of them on rivers. The RCP9 in the pic is only for reference, I think we'll be better off going with RCP8 for second ring, or even abandoning the idea of RCP altogether by that point.
- The red dot can become settler factory #2 after cultural expansion, it can claim a deer and a cow.
- The green dot can claim whales and a river mouth, but I'm actually in favor of settling on the light blue dot first, to grab the gems while also blocking the AI from the south.
- The orange dot is in a pretty weird spot but I didn't want to crowd the other RCP5 cities so that's where I put it. It can still get some decent food and shields after cultural expansion, although it won't grow very large until railroads.
- The yellow dot can claim the cows after expansion phase, and use it to support the shield-producing tiles around it.
- The purple and dark blue dots are included just for completeness sake, I don't really have much to say about them.
Oh, and if you think I was kidding about the culture flips, MapStat has this to say about it:
Not a single foreign border nearby, but the flip chance is already there.