Minecraft have only one type of PNJs : the friendly villager who love emeralds
For me a new type of PNJs will be really cool !
Mojang can add clans of PNJs who adapt their homes with the biomes : for example in the jungle they build their houses on the trees.
In the clans, there would be a kind of boss in each clan, a PNJ bigger and stronger than other.
They are hostile towards the players and other clans of PNJs and add a kind of war between PNJs , the game will be more alive !