If you can go back to August 2019

Add in Hyjal and Uldum zones (uniquely designed for a pre-cataclysm Azeroth), some more 5 and 10 man dungeons. Create a playable Scourge faction + exclusive death knight and necromancer classes. No nerfs or removal of content like SoM, but instead add more stuff. Flip the meta on its head, get people interested in trying new things and approaching things differently.