I worked abroad for several years after undergrad, then got policy experience and went to a master's program in DC. I would say international experience is essential for developing credibility in international relations or development field, but not necessarily so in being an administrator (though it should be) at a research institution that studies these topics.
Working as an administrator at a globally-focused research institute at a University is like working at a small nonprofit in that you wear a lot of "hats." Depending on the day, I'm doing communications or web content, admissions decisions, fundraising, writing or copyediting, helping produce events, budgeting or accounting, etc. It's full of ambiguity, which is a huge opportunity for those who want to be creatively entrepreneurial, and frustrating for those who wish to clear performance benchmarks.
Working at a University or research institution as an administrator provides lots of work-life balance, an opportunity for creativity and entrepreneurship, and it's just fun to be around smart people. Plus, you can feel good about what you're contributing to the world, similar to a nonprofit environment. People say the pay can be low, but when you account for the average work-life balance, I think it's really good (at a private institution like where I work, at least).
occasional international travel; lots of opportunities for free learning and training
Working at a University or research institution as an administrator can feel frustrating when colleagues don't work at a pace that is as fast as the private sector, which can feel demotivating if you are driven (but see the benefits of this above - easier to stand out). Smart people (faculty/researchers) are fun to be around but can also be judgmental. Most of all, there is quite a bit of ambiguity in many roles, and you have to carve out your path. If you need distinct benchmarks, you may do well in entry-level but won't advance. Also, it's frustrating when you have faculty or researchers in management positions. Honestly a lot of bad management from staff too.
If you advance to a central high-level administrator role, compensation is in the $200-300k range. It's probably greater at higher levels, but I'm not sure. If you work in a unit (not central), it will be lower.
Organization and creative problem solving because the environment is always shifting. Excellent written communication skills depending on your role and the ability to navigate ambiguity. Working at a University or a research institution as an administrator, you need a master's degree to advance.