See below for my responses.....
Thank you for prompt reply.
A. This was my first attempt. I am planning to apply this year so that my work experience will be 3+ when I take admission.
For now, I am unsure about a retake as my highest mock test score was 650 (right before the day of the exam). If I don't get scholarship/admit, I can take a few months off, prepare for 3-5 months and then attempt the exam again. That will also increase my work experience. What do you think?
It's becoming quite common to take the GMAT multiple times; schools take the highest score and worse case if you don't improve you can cancel and they never know you even took it again. But there's also a standard deviation of the exam itself... so very common, especially at 650 range, to be able to go in with a bit more prep, different questions different mindset and improve! It can't hurt to try and can only help, food for thought.
B. During test, I had sent my scores to:
1. Nanyang University, Singapore (Seems out of range now)
2. Macquarie Graduate School of Management, Australia
3. Ivey Business School, Canada
4. AGSM at UNSW Business School
5. Smith School of Business, Queens, Canada.
Why not Rotman, Canada: Because I figured it is above my average mock test score range, also it's fees is towards the higher side than the above two Canadian colleges.
It's up to you but your GMAT isn't actually too far off; that said without knowing more about your leadership and accomplishments etc it could still be a bit of a reach. In terms of fees, keep in mind some do offer more scholarships or financial aid so you don't always know exact costs until you get your offers.
Why not European colleges (Like ESMT Berlin, Germany which has very low fees): I want to know if language would be a constraint in job offers even if I learn German language a bit?
Not sure I'm entirely following; certainly at many top programs you can graduate and work anywhere in the world... but I suggest looking at each school's employment report (found online) to see where recent grads have gone, both in terms of industry and geographically. I'm sure it's EASIER to make local connections say in Germany etc, but still possible to go elsewhere too. For a generally-accepted best global MBA ranking, see the Financial Times MBA ranking for school ideas.
Why not UK/US: Stricter visa policies and uncertainty after study visa.
This varies a lot and is worth researching; in the recent past it was a misconception and school leaders from top UK schools for example have said it's not a problem at all for their grads to obtain visas to work in the country afterwards, in particular when a company wants to hire them. Just something to keep researching, and keep in mind many hiring companies recruiting at MBA programs are global multi-national companies these days, so you don't have to stay in the US or UK or anywhere, and/or you could get a job at a MNC and be placed in random countries.
C. Can you please throw some light on MIS (Management Information Systems) courses offered in the countries I have preferred above? I have friends applying for this course in the US through GRE and GMAT scores.
My expertise is really with MBA programs vs MIS and not sure exactly what the question is, but look for rankings and average scores online for those programs, which are generally smaller class sizes, and sometimes quite competitive but it varies.
Apologies for the long post.