zigzaggs,
The FAA is at the top of the list , the EASA is bottom for speediness of passing
You say you have a OZ CPL, what are you trying to achieve ?, if you have just passed the cpl you won't have enough hours for the ATPL anyway.
If you go the FAA route, you will also need to pass the FAA CPL as well as the FAA ATP, don't forget the new ATP compulsory ground school as well.
Ive done them all , if your in OZ and want to fly there , just get your head in the books and pass the ATPL exams in OZ