When I first received the Power Miners Mine Mech, I thought it was very cool and Exo-Force like, but it was also very very skimpy. So I added upgrades to the Mine Mech so that it will last longer against a dozen or so pesky rock monsters! Instead of a spinner that isn't good at drilling; I added a normal PM drill! The I noticed that the claws could use some more work; so I made them more dangerous. The legs and arms I improved plus I added a few defenses in-case a Boulderax rock monster shows up.
Remember: If you think that an instructions-followed model needs some work, don't be afraid to add a few extra pieces from your collection.