Copper wires and pipes

For instance they could add copper wires which would be redstone dust but blocks could be placed on top completely hiding them. They could also do copper pipes which could be a better item transport option than hopper so u could connect two hoppers without having to make loads of hoppers just to move ur mob farm loot 10 blocks into ur double chests additionally they could be used for decoration and who knows maybe if combined with bubble elevator mechanics they could even move items vertically with the help of soulsand and waterlogged pipes