Regarding the world building:
For what it's worth, without large scale civilization, precious gems and similar resources wouldn't be valuable enough to risk the lives of your community's small number of able-bodied warriors, especially when you could instead have them hunt. So some of their precious resources would simply not be worth the investment.
Inter-communal conflict in sustenance-level societies is exaggerated--warfare is costly. Obviously it can happen, but it seems the village is too far from other communities for it to be likely. The archaeological record seems to suggest that inter-community violence only becomes regular when resources are scarce and the communities are close enough to each other. With natural fortifications and distance between themselves and other communities, the yuri village is safe. Another village forming a warband and marching them over is basically requiring them to go without hunters for a few weeks.
Despite the fact that resources were stretched thin, if they made it to adulthood, people tended to live decently long lives if they were free from human violence, since humans have few if no predators and migration didn't happen enough that people would be introduced to foreign pathogens. (That said, child mortality was through the roof.)
While the story is very obviously fantasy, the idea of a peaceful hamlet living in a nice place during the stone age isn't all that unrealistic. Things like the quality of their clothing and their highly sedentary lifestyle though...