Look I love any game that we can terraform in but, terraforming is not exactly perfect. We need the ability to fill back in the holes. I'd be fine with that even if it went the way sort of Life is Feudal took where it gives you stacks of dirt. I would rather build a mound of dirt I might use later than be forced to jet pack over half of my base. The mining in the game creates GIANT holes especially at the beginning of the game. So ya, we need a way to fill them.