There really isn't a reason to explore very much, when you find a beefalo herd and some stone you can just camp there forever. There should be a really great reward for doing something that requires a lot of exploring. Like: Better light source that can be obtained by very rare thing(s) that are only spawned once in each world. (Infinite fire? large light radius?) Better weapons, armor, backpack or farming/cooking equipment made from rare materials (Unbreakable/fixable/efficient) Or maybe you just get research points for revealing the map?