We cannot learn archery now, because we don't have hunting yet (I went Agriculture->AH route). Actually I think that archers are not that much better then warriors. Warriors begin at 2.2 strength for us vs. 3 for archers, but they cost 22 hammers instead of 37 and we can promote with cover or woodsman after only 2xp. Also having more cheap units removes more fog of war then having fewer more advanced units.
So I don't think we need to change our plans now, let us go for BW. It will allow chopping and it will reveal where copper is. We have time to produce 8 warriors before starting the settler without slowing growth and can produce more if that is absolutely essential. Even if we don't have copper, we can settle the horses/sheep site to the SE and produce chariots which are mobile and strong enough to kill warriors and archers.
Sailing is another matter, whether to research it or not and when to do it will depend on what our WB finds north of Kyoto.
So I don't think we need to change our plans now, let us go for BW. It will allow chopping and it will reveal where copper is. We have time to produce 8 warriors before starting the settler without slowing growth and can produce more if that is absolutely essential. Even if we don't have copper, we can settle the horses/sheep site to the SE and produce chariots which are mobile and strong enough to kill warriors and archers.
Sailing is another matter, whether to research it or not and when to do it will depend on what our WB finds north of Kyoto.