If my 2c are worth anything....
You have chosen two very different paths but as you stated it in the beginning - your goal is to travel and see 30 countries by 30. That's six countries a year. I think your best bet would be to house hack your way to 4 properties and then take a "mini" retirement which would allow you to take 6 months off and possibly knock 10-12 countries off your list on one big trip. When you get back resume working and continue to acquire property. Then take a mini retirement again. Rinse and repeat.
An MBA will not help you achieve your stated goal. Period.
However, if you have dreams of accruing wealth. An MBA will give you the earnings potential to really invest and let compound interest work for you. But that is a 30 year play IMO.
I am going to grad school currently for a masters in engineering and it is significantly hampering my ability to review deals and focus on real estate. Energy is finite and at the end of the day, there is little left for real estate. Before I started my degree I was taking courses to become an agent. I think being an agent part time will get you to your goals faster than an advanced degree would.
If you are true to yourself and if your goals are sincere - save money like a crazy person and work even crazier. Work so hard that everyone thinks your are nuts. Anyone can work really hard when there is an end in mind. Invest that cash in property to hit your passive income goal, save money by being your own agent.
If you house hack and have "free" rent, you should be able to travel on a lot less than $3k per month.
When you get back from traveling, you could always get an MBA then...