re: Twin Towers II
As far as structure and use of space, the originals were superbly designed. Proposals to rebuild them all include serious updating of structural weaknesses, fire systems, and evacuation systems.
If somebody blew up the Statue of Liberty or Eiffel Tower, I'd like to think they wouldn't hold a contest for someone to come up with a brand new statue or tower, but rebuild them as good as before, or better.