I remember we had weapon skins of some sort in retail. Could we re-implement weapon skins as a new costume slot item. Some players do care about the appearance of their weapons, but make sacrifices for the stats; this change would make your weapon appearance consistent and pleasant to view no matter the changes in gear.
The food, utensil and candy weapons were all originally retail skins. You could make the food and utensil skins tear items, candy skins moolah items and you could also develop new/cool skins for moolah/dungeon drop (golden temple?)/magic tower token rewards/etc.
Edit: As a side comment, you don't have to add stats to it. You could make it a stat-less costume piece solely for appearance. Or add stats if you wan't, totally up to you, but I know balance/overpoweredness is always a concern when adding a new costume piece.