Nobody really left because legion was "bad". They left for a variety of reasons(running out of things to do, etc), it only seems like ppl left over it being bad because those are the outspoken voices. Anyone who leaves for a perfectly understandable reason isn't going to go to 15 different wow forums and QQ endlessly. Those who quit b/c they think it's bad do. Anyways, the reason Legion was better received than WOD is b/c WoD was absolute trash.
- Horrible ass raids
- Garrisons became the focus of EVERYTHING in the game
- The wow economy went to absolute crap directly due to the fact that it was raining gold from the garrisons and everyone became a millionaire almost instantly
- The constant back peddle on flying (no flying, maybe flying, no flying, ehhh, yes flying, lulz not until the end of the expansion)
- Shipyards were poorly implemented
- The gear was beyond ugly. Show me 100 different weapon/armor models and maybe 5% per 100 are half decent looking
What it got right:
- I could level alts from 90-100 in less than 2 hours once flying was implemented thanks to the exp potions and bonus objectives. Managed to get every class to cap, feltgood.edu