I have idea for use of coins:
Create a Hall of Fame - the list of 10 or maybe more? 100? most powerfull villages / players.
The "power" = the coins the village have. That might give the coins new usage and value.
And more, maybe the village money could be spent on altar to give some boost to villagers?
Or maybe - who is higher on the Hall of Fame list - gets more boosts (to LP, or skills , attributes?), constantly.