What do you mean by starting point? You are both in Australia so that will be the starting point for a LONEx.

Vanuatu is not possible on a LONEx as there is no OW metal to there. Actually, other than New Caledonia and PNG there is almost nothing in terms of pacific islands which can be done on a xONEx (a Global Explorer would be required for flight in this area).

Maybe looking at a *A RTW might be a better option? You could fly something like SYD-SIN-JNB-LHR-FRA-SEA-LAX-RAR-AKL-SYD (and some side trip) and also get much more miles as this books into H class.