I think it was just the separating of content that made it feel shorter than normal. Usually having to do a dungeon mid MSQ makes it feel longer because well, you had to go and do that dungeon. In terms of story progression, not a lot really happened as it was more character focused than the narrative. It would have been nice to have some more idea of "what's next" though as it feels like we got an extended cliffhanger from the end of 4.0.