I might have a few suggestions for armors to be added to the game as items, feel free to post your own in the comments.
All of the chaos lord armors.
Possibly the lionfang armors.
Doomknight armors (Ex. Ornated)
The 3 verification sets (Starlord, Dragonlord, Guardian)
I would love to see some older armor sets to make a reapearance, seeing they have a niche distinct artstyle that is rarely seen in new AQW sets.