NPCs have unique IDs and other identifiers so if you wanted you could build an AI for them, a crude way of doing it would be having a timer and checking/setting their position every few seconds
The first problem I see is that there is no NPC raycast to allow you to make them walk around obstacles.
Then ofc there should be methods such as NPCChangePositionEvent, or NPCCollisionEvent to handle things.
Most importantly I think an NPC inventory is missing with proper active slots like they player one, if that is implemented you could then have for example NPCs wielding picks mine for you, or wielding axes chop trees for you etc.
For now I think you can settle for making an NPC follow you or add small interactions when the player hits them