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My suggestion is that a GPS system should be added. What I mean by this is instead of having more that one map, have a gps that runs off of a satellite that is made by the player. The cost of GPS should be like a diamond some glass and a stick or something similar. Just think of all the cool possibilities for a gps. You could add way points and cave maps; even adding speed and direction would be awesome 
And it should have to be recharged every so often. It would be epic if this was added, just to see all the terrain you have discovered in one inventory slot. EDIT: sorry about the issues, my search didn't actually turn up with anything. my bad.