Combat Addons and WeakAuras: Blizzard is severely restricting access to combat data. Many classic combat-related addons and complex WeakAuras or damage meters (like Details) no longer function as usual in PvE.
marvolomania
+1
Blizzard's own UI tools: As a replacement, Blizzard is integrating native features directly into the game, including a new boss ability bar, a damage meter, and a cooldown manager.
YouTube
·Vegabundo
+2
Class streamlining: Numerous classes and specializations are being significantly streamlined. Superfluous or redundant abilities—as well as excessive cooldowns—are being removed to reduce complexity.
marvolomania
New level cap and zones: The level cap is rising to 90. You will explore revamped and new areas around Quel'Thalas, Eversong Woods, Zul'Aman, and the Harandar Jungle.
World of Warcraft
+2
New Demon Hunter specialization: Elf races can play the new mid-range Demon Hunter specialization, which utilizes "Teachings" instead of Fel energy.
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·Vegabundo
Housing and Transmog: Personal home building and furnishing are being introduced. Additionally, the transmog system is being overhauled so that outfits can be saved and swapped for entire slots rather than individual items.