I liked the effect, it was kind of like how a Meth addict becomes gaunt, pale and prematurely aged. Very creepy.
As for bringing them back, who knows what is possible in another plane of existence where all time and place can be experienced at once? As for Brink being old, he DID fall off of a cliff. That, and I like to think, in his 2 deaths, and psychological degeneration as a result of the crystals, something was lost from his original self, and that should have SOME physical manifestation.