what always seemed to be the reason the powerful didn't take the ring to use against Sauron is that the more powerful the being, the faster it would corrupt them... absolute power corrupts absolutely.
Is it Galadriel or Gandalf who says to Frodo when he asks about peering into the minds of others and controlling them, that he would have to become vastly more powerful. I'm Sure its Galadriel.
Gandalf, i always assumed, used his ring often, as a strength to help him in his journeys. But the elven rings were NOT created for war or dominion, but to preserve and support.
Aragorn, unchanged? No i think not. The Hearts of Men are easily corrupted. And Isildur fell VERY quickly to the ring. Aragorn might last longer, but he'd fall too. Like Galadriel, in place of a dark lord Middle Earth would have a King, not dark, but handsome and terrible. All would love him an despair. Although, Aragorn was not a powerful individual anyway from all sources.
Certainly though, at the time of the War of the Ring, if the One Ring had come into Galadriel's hands, the Middle Earth would have suffered more than it ever did under Sauron, or could have under Saruman. Her innate gifts of perception, would have made her know all, see all and destroy all. She is at the time of the War, the most powerful of the Elves and its never clear whether that means she's stronger than either gandalf or saruman (when either was white).
