What I would include:
Ogres, Vrykul, Naga, Drakonid races
Necromancer, Dragonsworn, Tinker, Runemaster classes
Player Housing, Shared Void Storage - basically a shared Battlenet bank
Skin Color change in Barbershop, Blue Fire option for mages, mechanical chicken starter pet for goblin hunters
1-40 Item Overhaul - make mail items real mail items not leather reskins and introduce proper 1-40 plate armor
Bard Profession - craft songs, perform theatrical plays, write books, play instruments, dance, entertain
Make Glyphs become player colelcted items through quests, drops, pve, pvp content or obejct loot - have varius ways for various glyphs
Make reputation account wide - with Heirloom items - Badge of Commendation for example
New race/class combinations: Ogre Priest, Tauren Mage, Tauren Rogue, Undead Paladin, Pandaren DK Draenei Warlock, Draenei Rogue, Night Elf Paladin,
Gnome Shaman, Orc Druid, Human Druid