Hmmm, I am going to pretend to be logical about this...

With H&H we needed areas that were unexplored areas of the plains for tar.

With the addition of Mistlands, etc. those will need to be unexplored as well.... BUT..

that starting point.

We have all been to the starting point were trophies are hung, and the addition of 3 new bosses (one for each biome) means new stones at the start point, and this area will have to be updated.

If the starting point has to be updated, that means the whole world will most likely need to be reset.