The island up north was supposed to be home of the breakers, and was going to contain a lot of story content involving them and Yrel. It was cut in alpha and merged with Gorgrond, which is why Gorgrond feels like its two stories that are half assed: because thats exactly what it was. Its also why Doomhammer just suddenly appears and dies: he was supposed to have a lot of story content in Gorgrond which was cut when it merged.
The island down south was the Warsong homeland. You may recall that there are a LOT of warsong weapons we cant get in game, we also cant get the warsong snarler which is in the data files, and the Warsong despite being the "head clan" of the iron horde did largely nothing in all of WoD: because the intent was to give them Faralohn (the southern island) as a patch.