Maybe we are making a mistake in thinking that the best use for the planet would be as a "sister Earth"
What if all those buckyballs, or carbon nanotubes could be used to manufacture something that could not, or would not ever be manufactured on Earth?
Could Venus by utilized as a giant manufacturing plant where products that could never be manufactured on earth could be easily manufactured on venus?
Maybe venus could be the key ingredient in a space elevator for the Earth, Moon, and elsewhere?