There are many matters to consider, the main one being, where do you ultimately want to live? Having decided that then you need to optimise your chances of getting a good flying job in that country.
Quality of flight training then becomes a key issue along with whether or not you want (or will need to have) a university degree.
If you want lo live and work in the US I suggest do your training there. It is cheaper and you will find it easier to get into the system if you already a resident.
In Australia you will have to become a resident in order to get a flying job. This is not straightforward as pilots are not on the list of jobs where migration is a priorty. However, there are flying jobs flowing and growth in Aus will likely remain buoyant because of the SE Asian growth factors, but there is a lot of competition. You get get a student visa to study here quite easily provided you study full time (or at least 75% of full time load), but there is a points system for resdidency (check the Aust government website). If you ultimately want to live and fly here, I suggest you do your training (and education) here.
I live in AUS because it is the best country to live in and tolerate our higher taxes due to the large country size and small population as the price to pay.
Generally, we have very high quality flight training and high quality university education
[stru youdoneed a decree to flyaplane but fucan getxtra mental capabibibilities then mabee uhav xtra gud options].
Aus is a great place to live.
good luck
Seabreeze