In this thread I aim to explain why and how it should be implemented.
So how should this be implemented?
1. Add a 5th tab to the blacksmith interface: Customize Armor. It should look similar to the repair interface. There should be an item slot for the item you want to change, and a drop-down menu to select the item's new appearance.
2. Here's how you do it: You put one of your items in the slot, select from the drop-down menu its new appearance, press the button to pay, and voila!
3. It does not need to be expensive. Inferno dyes cost up to 5000 gold. The cost of changing a single piece of armor should be the same.
4. You cannot make your armor look like a legendary (or a different legendary), one of a higher item level, or one for a different class. It makes no visual sense for a level 10 hero to walk around in Archon armor, for example.
5. Class-specific items or legendaries should also be able to change appearances, provided they meet the conditions in 4.
6. Once put on an auction house or into a trading window, the appearance of the item reverts temporarily to the original.
7. Obviously, only identified items can be changed.
7. Dyes should remain constant throughout.
Take a look at this:
Each class has at least one hundred unique, three-dimensional, and fully textured armor models. But most players end up using only 18 of them. That is to say, they use only the level 60 items.
That's 72 armor models, per class, practically wasted! Players use them for a couple of hours as they level up, then forget about them once they reach level 60 because they do not provide the stats necessary to survive in Inferno.
Also, most pieces of armor are themed based on level. Items on the same level fit each other visually, and wearing them at the same time just looks cool. That's around 12 different item themes per class that level 60 characters never have a chance to use.
By allowing players to change the visual appearance of their items, these themes will be reintroduced to high-level heroes, and those who do not wish to use them will still have hundreds of new item-combinations to make their heroes look the way they want them to look.