This actually reminds me of DC Universe Online. The "glamour" system there was pretty simple and I hoped FFXIV would be similiar to it. Every piece of equipment has some sort of "look" attached to it, which if equipped once, is saved on the character. Those looks you collect as you collect equipment. Once equipped the equipment gets bound to you. Now as this could be a problem in situations like "I want to sell this robe but I'm gonna wear it first just to see how it looks" there could always be the option (here comes what the OP said) to save the glamour of the item (with the help of an item, the glamour book). In DCUO there was a menu (which you could access at all times) which listed all the looks (and hairstyles you could buy with in game money and I think even being able to adjust skin color) you could change the appearance of your character at will. You could also "lock" your appearance so if new equipment was equipped, it would keep the appearance of the old gear.