Congratulations on your admits, both schools have excellent reputations in the business world. Based on the factors you have mentioned, here are my thoughts:
1. Goal: Both Duke and Oxford have a strong reputation for placing students in consulting, including MBB. So, either school would be a good choice in terms of achieving your goal. However, it's worth researching which consulting firms are actively recruiting at each school, as well as the strength of their alumni network in your home country of Indonesia.
2. Academics: Oxford's one-year MBA program is rigorous and comprehensive, covering all the essential areas of business. While it may be shorter than Duke's two-year program, the program's intensity and focus may be better suited to your goal of quickly gaining a strong business foundation.
3. Placement: As you mentioned, Duke has a higher number of full-time job placements to MBB from their MBA program, but that doesn't necessarily mean Oxford is not a good choice. Oxford has an excellent reputation globally and is well-known worldwide, which could be a valuable asset when seeking employment. Additionally, the smaller size of Oxford's MBA program may provide you with more personalized attention and opportunities to connect with your peers and alumni.
4. Work-life balance: Both Duke and Oxford are top-tier MBA programs, and as such, require a significant time commitment. However, Oxford's one-year program is more condensed, which could potentially provide a better work-life balance than a two-year program like Duke's. I know how intensive one-year courses are. I have been really juggling between keeping my life separated from my school life.
In conclusion, both Duke and Oxford MBA programs have their unique advantages, and the decision ultimately comes down to which program aligns best with your career goals and personal preferences. I would recommend researching both programs further, connecting with current students and alumni, and ultimately choosing the program that feels like the best fit for you. Good luck with your decision!