I like this idea. Having unique glamors unlocked after reaching certain milestones would be fantastic.

One thing that should be restricted though are the types of reward offered. They should be purely cosmetic or minor convenience items, nothing which directly affects gameplay to any strong degree. Things like teleport tokens are fine, high level weapons or rare materials are not.

For those who aren't interested in achievements, this won't affect them. For those who are casually interested, like myself, it's a nice bonus. For those crazy achievement hunters, it's a blessing. Either way, it's a great idea and one I would love to see implemented.