Genuinely?
Graphics update
MSQ
New glamour
New housing items
Maybe extremes / savages
Maybe side quests (I really enjoyed the shadowbringer job quests for example)

Because dungeons, raids, and alliance raids I will do once, maybe twice, and then never again, unless I want the glamour or the tomestones. :/ (What really kills me is having to repeat content daily, weekly, for the farming of things. Just sucks the life out of me.)