The way they implemented the combat ally in Legion really helps make legion world quests feel more rewarding than BfA world quest right now.
Opening boxes or even activating Artifact Power felt more rewarding than seeing a text about gaining 150 Azerite Power.
They've gone full pendulum away from quest hubs. BfA has no Nomi to burn our food, no Farmer Yoon or Tiller's Union, no wretched buffs or army training. Modern quest hubs not only help tell a story, but they can grow and evolve over time.