Build on the Ivory, and it isn't close: it picks up the game tile, which has to be at least as valuable (if not more) than the flood plains. Also the BG, and the river forest. We do get a river mountain tile, which isn't great, but I'd rather have that other stuff than the coast and flood plains. We are giving up some far-distant population (which would translate to about 3-4 scientists per turn) in exchange for greatly increased production. Most importantly, if you build on the ivory you are going to need a cultural expansion (which we haven't got time for) before it can get ANY BGs or anything besides the ivory and the fish. Our production there will suck until that happens. When Moscow expands, we pick up (I think) one bG.
I'd gamble out the CoL/Philo slingshot, though it's not necessarily clearly gettable right now. Vikes will almost certainly go for Mapmaking, but the Inca could get lucky and pop Philo from a hut, which would be unfortunate.
Moscow needs to pump out workers for a good long while now (at least six, probably more). We need to connect land, road up, and mine the heck out of Novogrod and the ivory town.
As discussed much earlier, I'd go warrior/warrior/(warrior?)/prebuild in the ivory town. Not sure about the third warrior. But we need to get MPs in place in our cities and get the SoZ moving ASAP. I'd let Novogrod continue on the Colossus. Getting both would be a big boon to us in the long run, and I think we can afford to try.