I also come from a Business Administration background.
Our bachelor's doesn't make us come from an over-represented pool, freshers joining masters as soon as they are done with bachelor's might be seen as one.
But then almost 60% of students do MIM/MSc just after their bachelor's, so no one is exactly under the over-represented pool. What can make you unique is your experience - Work or extracurricular, your GPA, Volunteering Experience, etc.
You are selling your profile. So in place of worrying about being over or under-represented, strengthen your profile in any way you can. There is no such over and under-represented stats for Masters except for those who are looking for a career change.
Regarding which round to choose, R1 is always beneficial, but if you think you could work on your profile better till R2, R2 won't be a deal-breaker either.
Posted from my mobile device