Personally,
- I loved the zones & music, aesthetics & lore.
- Warcraft 3…duh.
- I actually really liked Wrath dungeons. Not all, but most,
- Class Balance - after TBC, it’s like a breath of fresh air. Almost every spec is viable in PvE, including Feral Druid.
- RDF and leveling alts with it.
- Warrior’s Warbringer talent (charge in prot stance)
- 70-80 questing experience, imho, is much much better than TBC 60-70.
- Dual spec
- Raid difficulty modes - allowed all types of players to find raid spots.
- Though not a fan of Ulduar myself, I loved ToGC raid. That was like the perfect raid for me.