Hello Demortalizer here with some suggestions,
1st : You could try add a aoe looting system of some kind.
2nd : Do so all classes can be all the races like since i play shaman id like to go worgen or human.
3rd : Not sure if this one is good but add the MoP dungeon challenge gear sets for transmoggin, could be a loot from hard boss or a long quest line.
Kind Regards
Demoratlizer.
You guys should add new content or so and make new tier of armor with gold challenge sets for ea class, that you get from upgrading the impec would be so epic :).