Congratulations on your great gpa and GMAT Score- certainly high points of your profile. You have significant international experience as well which adds more value to your profile.
As for your concern about extra curriculars, I do not think you need to fret about your" lack" of extra curricular activities .
Quote: "I have competed in various triathlons since 2006 and practice amateur photography, cinematography and creative writing (only as hobbies)"
This evidences your participation in extra curricular. I don't understand what exactly you mean by common or uncommon. I understand that these MAY NOT demonstrate leadership . However, for leadership experiences, you need to retrospect and dig deeper to figure out times when you took initiative, motivated someone, or did things to resolve people's issues etc.
Second, if you have done well in academics and progressed consistently in your career with significant accomplishments, 'lower profile university' or 'relatively unknown company' should not matter.
Lastly, even though your first and only choice is Ross, I would recommend you should have some back up with you and apply to 1-2 more schools. However, if you still insist on applying to Ross only, please do not mention it in your essays.
I hope it helped.
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