Hate to burst your bubble but there's a lot of effort put in the tier gear as it currently is, so this would be really time consuming and expensive. Although on a second thought, the artwork would need to only have to fit on one race, so there's less QA. Thing with GW2 is tho, they allow the player to apply their own colours, and this concept I really like. So only the actual artwork and deciding different parts to contain the same color (C1, C2, C3, C4 etc). Still, its a big change from how WoW is currently. I hope new MMOs will follow a different path.
(And get rid of the female breast visible in plate; its just not how plate is worn by females, and it doesn't protect the female at all. Its actually dangerous.)