Click and Drag Material Swapping
For this idea essentially you would be able to click and drag around an area, pick which block and then the block you would like it to be. Should you come out with a material i like more for instance my Burial Chamber would be an unholy nightmare to swap out the blocks whereas with this feature I would simply click and drag and have all wood blocks swapped out with Obsidian? Bones? Solid Metal? (Provided that I have the needed materials and maybe the feature tells you how many half and full blocks of that type you need to fulfill the order)
Could be handy
As discussed in the chat this could be a very convenient way to upgrade a building. The system could incorporate the original cost of a block. So if you designated all Cement blocks to be changed to wood you'd need the funds to upgrade the blocks 4 coins each. The system would tell you that you need x amount of gold to complete the request and you just go from there.
yeah I figured it's a nice alternative to completely disassembling a building entirely just to swap out the blocks