Im sure you gave it some thought, i mean honestly with the current rate players on the Settlement world is already fading away. I am suggesting this because i fear if more players join and keep getting resources from underground that within a week or 2 depending on mining rate the current world would be rid of diamonds, emeralds, iron, and gold. (Lets admit, i dont think coal would ever disappear lol). In all seriousness though a Resource World wouldn't hurt too much, and would help with...
Resource World
Resource World