I would love to see some sort of permanent upgrade - maybe like a tech tree upgrade system. It gets rather boring, doing the same thing for the first 5 minutes and then hoping you can complete your tasks.
Pretty good game, I like the controls. On the other hand, how is this game like Motherload? Yes, they both follow the same concept, digging into the ground and getting resources, but there's more than a few games like that. The only similairity is the concept. 4/5, pretty good.