For the inventory issues I have come up with a pretty good system. Two bags you can make early game. I went with easier bag, then updated it and now I have a full inventory back (in the bag only) Blue power also has a bag, it cost a little more string but string is easy to make with Stick, bowl and saplings. Then add a Dev/Null to get only carry one stack of cobble while mining and all your inventory issues are solved. Both items are dirt cheap to make.