Personal opinions ofcourse.
1.Old Night Cycle, The older ones who we all have seen awhile ago is alot better and makes you feel like night is dangerous and actually scary then just how it is now, you can't even see the difference between night and day if you dont look up the sky.
2.This is really personal but i think they need to add back the staff/polearms hunters could wear before MoP, I myself loved to had something on my back it felt like my hunter felt strong they dont need to add back like stats or something but a way to have a staff on your back would be amazing.
3.Remove level 90 guards from towns. I saw a screenshot where lvl 30ers were attacking the barrens, i think that is pretty cool and even new players who are leveling can have a little fun by attacking towns, not everything should belong to max levelers only.
4.arena skirmishes should be added back in the game, it was for funsies and was pretty relaxing but fun same time.
5.Being able to control your pet back in the days was pretty awesome, that skill they should have never been removed.
What do you guys would like to see back in the game?