Having lived in both countries here is my perspective. There is hardly any difference in terms of work culture or access to countries. I think Australia is doing better financially. But both countries have great natural reserves and will do well .. You would probably earn a bit more compared to what you would make in Canada, but you pay more for everything too 🙂 Weather wise Canada has harsh winters but if you like winter sports you would probably start enjoying it. Both are great countries, there is a lot to see in both countries and a lot to do. Both countries have cities consistently ranked in top 10 livable cities of the world.
But I chose to stay in Canada due to my personal experiences in Australia. In just 1.5 years I faced numerous racial taunts. Once on a Friday night a bunch of morons threw eggs at us. In general people are more arrogant in Australia. I found Canadian culture much more welcoming and respectful of diversity. In my 10 years here I have never faced anybody taking a jibe at my race. Canada is truly multicultural and Canadians are the most amazing people in the world. For me this was the most important reason to choose Canada over Australia, as I thought my child will get a more tolerant society/environment here and won’t be subjected to racial slurs.
Good luck on your decision.