Hi there!
Let me try to answer your questions...
1. One year MBA is more cost effective, but it typically works best for individuals who are not making a big career switch, because you don't have time to do an internship like you do with a 2 year program.
2. There are lots of rankings out there! Personally I don't believe one is better than another, and it depends on what programs you're looking for (e.g., for global programs Financial Times is more comprehensive). I also think you should look beyond the rankings to determine how you fit with each school. But another option is to check out Poets & Quants rankings, where they aggregate all the others:
https://poetsandquants.com/2014/12/01/po ... l-ranking/3. Check out our guide to selecting target programs for some criteria to consider:
https://shop.mbamission.com/products/sel ... ba-program4. Check those schools' career stats to see where their grads go, and see if you can talk to some recent alums to find out what it's like to be a career changer at one of those programs.
5. 16 month MBA could be a nice in between option for you, many programs in Europe are the same, and they may allow you to do a short internship.
6. I honestly don't know much about programs in Australia...in Canada some of the top programs are Schulich, Sauder, Rotman, Ivey, and HEC Montreal.
Hope this helps, and good luck!