Here's what I've come up with after attending both student days if anyone is still interested or is in the same situation!
Yale:
very small class (150 incoming students), and you can make personal relationships with your classmates professors. There's a very vibrant community spirit there. There is also a large selection of electives you can choose from and more opportunities to take courses outside your department (in the public health program and also in other yale schools). Lots of research there too, as most departments require a thesis. They make the effort to push their students to network both inside and outside of new haven. Students there are more able to carve their own path in their public health education and their focus within in (while also having to take core courses acorss the MPH program) Also, the cost of living is much cheaper.
Columbia:
much larger class (500 incoming students in the MPH program, more if you include PhD and accelerated 1 year track), but they have 20-30 people in their seminars. Faculty and students arent as close but they are very open to doing research with students outside the classroom, so the opportunity for personal relationships is still there. The curriculum is much more rigid - your "electives" are confined to your certificate, and outside of those there are only a few more elective spaces you can take in other departments/schools. They are very mission-focused, the "MPH factory" feel is very apparent there - where they create the "perfect public health professional" with their core curriculum and projects. And, NYC is a national hub of networking for public health opportunities, so Columbia takes full advantage of it. Cost of living is what you'd expect for NYC.
At both, no shits given for international funding but this is expected.
Does anyone have anything to add? Did anyone get a different feel from what I suggested?