Here is some stuff that should have been in game...a long time ago.
Cloaks that show in game
Cosmetic armor for Nerco/wolf/iron defender pets that make them look like something else wolf > lion
Racial Enhancement tree combat pet...humans/dogs WF/iron defenders dwarf/wolverine at the top end ect...
Spears and polearms
The return of mithral armor and med/heavy armor options for druids
Monk feat that allows light/medium armor - Samurai enhancement tree NOTE - can be a bonus tree that you can open
up, like AA with at least 5 points spent in both a monk and a fighter tree
Premium member should be able to open dungeons on hard
Give bows a reason to exist vs Heavy repeaters
Pure cleric specialty ability...treat similar to half elf Del.
Evil alignment
Black Guard Enhancement tree for fighters?
Crafting = drop loot if it drops, it should be craftable as well
Massive lvl adjusting random dungeon (Undermountain)
The ability to start an epic character at level 1 or purchase that right
All of this should have already been in game considering how long it has been out.