Get the raw stuff back from blocks
It would be great if we had a way to get the raw materials back from giving blocks. I know you can by the stone road, but nothing else.
I would be OK if you get a little less, and would need a skill to get the equal amount back. Think of it like recycling.
(BTW this might be the answer to the tailing problem. By making a recycling tool, it will turn them into dirt or sand)