Why not build the third new village upstream, so they wouldn't have insane treck to the main village? That way the first new village could also work as sort of a hub.
It was actually mentioned in WN - people said to him that putting a new village upstream from main village would be wrong,
basically because they take water from the river and drop waste there, so putting a new village in control of your water is a bad idea.
@Vodoka On chapter 63, They decided to create the first new village downstream, because of difference in rank. This means that newer village will never be built upstream of Taiju village