We need to give the pathfinding a little overhaul and create a proxy between pathfinding and AI.
The proxy would:

• Recognize when a Path won't reach the exact destination and first try to path close to the target and then to the actual target.
  (Could use player-set waypoints (roads?) and colony buildings)
• Recognize when a Path won't reach the destination at all and tell the player.

Pretty much done:
Missing

• Miner should also use all the nodes to navigate.

Should be done now.