Correct me if I'm wrong, but didn't Skyrim engine renders the world in cells? So theoretically, The size of the world would mattered little, since Skyrim only processes only small parts of it, so computers would be able to run it normally. Besides, we may be able to extend Skyrim script using SKSE. True, part of the issues is filling the "in-between" areas, this could be accomplished by: 1. Getting help from hundred of modders :D 2. Randomly generating landscape. "Nothing to see" is exactly one of the purpose of this mod. It's not so the game would be more fun, but it's for immersion only :D, the Earth is full of "nothing to see" areas. Plus the tedium is solved by free fast travel (you can fast travel to any point on the map, discovered or not)