Well, they chose 4 specifically and I have it as theory because in Chinese, 4 means death and 4 is in the game alot and does it so happen that Mr. Myomoto is Chinese and so is Aonoma. Its like a religeon I think, found it off of Artemis Fowl and reminded me of Termina. But your right, the moon dungeons don't really count and they should of had Link go off still searching for his
friend and finding more origins to the game. Wait the game is really focused at Navi and I don't mean I'm stupid and just figured he was looking for her, but that it seemed she was still around or she had a more important thing to do there. I think maybe they could make a sequal of Link still trying to find Navi or include it in.