[Susiron]

Option 1.

I'd say Option 2 if the old world could be placed in spectator mode rather than adventure. I'd like to be able to fly around so that I can see all the details of my taller builds and replicate them. It will also be useful for viewing old builds underground or in closed off locations.
I know that it says Experienced+ would be able to go into creative mode, but spectator seems much more practical and fairer to all players.