If we continue the war with Mao he will probably capitulate soon. If he becomes vassal of someone else it will start another war. If it is Alex, it might be good for us as we wouldn't have to declare on him. I am not sure who else it could be but there is a small risk there depending on who takes him. I don't think we should take him as a vassal if he offers as it would give us a negative modifier with all other civs.
I agree we don`t want Mao as a vassal. If he becomes a vassal of someone else, the only plausible candidate is Alexander as everyone else either does not like him enough or is not powerful enough. If he does declare war we may need to whip out few extra units in Bejing/Shanghai to hold those cities.
Do we want to upgrade some triremes to caravels so we don't have any nasty surprise? It is pretty cheap.
I would upgrade the triemes, and send one to contact America, it could scout the size of Alexanders reserve in his capital on the way. We could upgrade the galley to a galleon at the same time. Maybe we could ask some of the civs we are pleased/friendly with for a gift of money to pay for this?
If we seem to be running short to get the GE, maybe trading for Steel and putting in the Ironworks will help with hiring more Engineers in St P. I think a switch back to producing GE points in St P now might be a good idea, as it will cost us less GPP to produce him now as compared to later.
This would require a major tech detour to Chemistry as well as requiring us to build 2 more forges in low productivity cities. The Ironworks costs 1050 hammers by itself, so building it will take a long time. An easier way to get a Great Engineer would be to remove all the specialits in Moscow. If we do this then St Petesburg will produce a Great Engineer in 25 turns time. If we did this we would want to build a university in Moscow before an observatory.
we need to delay the engineer in St. Petersburg anyway as all gpp produced there after the engineer pops are wasted.
I don`t think that matters, we are only ever going to generate one GE in St Pete, so whenever we get it the effects are the same. Delaying it will only make it more difficult to generate the engineer in the future.
Another interesting tactic to pursue would be to build a Confucian and Jewish monsatery and see if we can split the field a bit more by spreading religion to other cultures. breaking up the Buddhist and Hindu blocs seems to be a good way to get more votes for us.
If we did this it would have to be soon, as scientific method will stop us building monastries.