Hi-- thanks for your post!
You've got a good start for a solid profile.... let's break it down further.
-solid academics & GMAT (necessary, though not sufficient
, to gain acceptance to b-school-- you have to show you can handle the academic rigor of the program of course)
-there aren't as many applicants coming from Australia at US b-schools
-analytical & quant skills
-project management skills
-experience working with others/clients etc
-ensuring you stand out from the crowd and that your app is 'remembered' so to speak. Spend some time brainstorming about all aspects of your life and what makes you who you are; and what you bring to the table that maybe others do not, and aim to get that across in apps. Also really work on those essays to make them engaging and memorable.
To your q's:
1) HBS could be a challenge, yes, in my view; not that you have major weaknesses per se, more that they get SO many very strong applicants that it could be tough. Generally your school list otherwise sounds reasonable, though possibly long, even when split over 2 rounds... just be sure to keep in mind how much time each app can take, and that essays differ, and also that your recommender will need to put in that much time too (or have multiple recommenders).
2) Sounds like additional international experience; sounds good to me!
3) I would not worry about the 5 IR.
4) Yes could be stronger; at this point there's not too much you can do unless you go get involved in something now.
Just do in depth where appropriate about what you DID do, and maybe what you plan to be involved with on campus where it makes sense.
Good luck! Let us know if you have any questions or would like to speak further.
And enjoy London if you go-- lived there 3 years, LOVED it!
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