I like Option 2 (unless you get much out of an overnight in ICN in Option 1) if trying new products and getting back quickest without having to wake up early is the goal. Option 4 sounds good if you'll be in the Gold or Sunshine Coasts, but if you'll be in SIN or MEL you'll need to add a segment making it an extra stop. However, if the goal is to burn AA pre-deval and not get back the quickest (or just to try another EY product).