Again, there’s no bad choice here. But I’ll give a JHU perspective.
Normally discussions with JHU involve debating if the higher tuition costs are worth the benefits, in this case the fact that JHU is cheaper makes it all the more enticing in my mind. All of these schools have strong premed programs and are large feeder schools into medical schools, so as far as premed benefits (I believe all of these schools offer committee letters) I think it’s a wash and wouldn’t worry about that. Med schools compare apples to apples (especially when they have so many applicants from these schools each year), so whether you go to a school that inflates or deflates GPAs or go to a tougher but well-known program like JHU BME has little bearing (in terms of admissions) since you can easily be compared to 1000s of your peers just from the past few years (let alone hundreds in any one admissions cycle). Medical schools make it a top priority to find the most well-qualified and diverse class of students as they winnow down the 5,000-10,000 applicants they receive for the 100-200 spots they have. Don’t be tempted into thinking that a school well-known for GPA inflation will sneak under their radar. That being said, attending a school that makes you work hard and forces you to develop strong study habits is very useful come time to hunker down for medical school (and I believe all of these schools have hard-working students and rigorous programs). Again, a wash from a premed admissions perspective. Has much more to do with you and the effort you put forth at these schools rather than any minute differences in counseling resources, program ranking, etc. There are many paths to medical school and I would focus on an undergrad institution for the sake of being an undergrad institution, not just as a stepping stone to medical school (which is a common thing for people to do).
Don’t forget that often the #1, #5, #6, #8, #9, and #10 most popular majors at the JHU School of Arts and Sciences are International Relations, Economics, Writing Seminars (Creative Writing), Political Science, History and English, respectively. Hopkins may be known by the layman for the engineering and sciences, but it has a great mix of stellar and well-respected programs that undergrads (and grads) study. Hopkins describes itself as a liberal arts school with significant amounts of “distribution requirements” for graduating that require students to take coursework outside their program focus. For example, I was a Neuroscience premed major and I ended up taking two creative writing classes, a Philosophy course, two years of French and a half-dozen History of Art courses (I doubled majored in History of Art at the end of the day). Hopkins brags that about 20-30% of its students each year double major, largely because the school requires you to complete coursework in other areas and students end up finding interests and pursuing them only later to realize they just need a class or two and they have the second major. Whether a second major is actually useful in the real world is another story and is a case-by-case basis.
If you’re interested in Public Health or IR, then I would say Hopkins is a great place to be. Bloomberg School of Public Health and SAIS are the JHU graduate schools for these programs and are #1 and #2 respectively in the country (SAIS is typically considered second only to Georgetown’s SFS, though this is debatable and there are other great programs too, like all rankings). Strong grad programs typically have a direct bearing on undergrad programs since they can significantly impact program funding, attract undergrad students passionate about the discipline, and have spillover of stellar faculty and opportunities to take grad coursework and participate in grad research. This is definitely true for Public Health where undergrads are actually required to take coursework at the graduate school and many get involved with all the research conducted there and in the city of Baltimore (one of a few public health researcher’s dream cities for all its problems and opportunities given the willingness of the city to let JHU conduct research and take on big projects in urban planning, inner-city education, etc.) SAIS, on the other hand, is all the way in DC. I’m unsure how this grad program directly benefits the undergrad program; however, the IR major is the most popular undergrad major at the School of Arts and Sciences (more than Biology, Neuroscience, Public Health), so it must be for something. Some students apply Sophomore year to the five-year BA/MA program where you complete your Master’s at SAIS your last two years, which is not a bad route to go if IR ends up being your interest.
As with all of these schools, collaboration is emphasized at JHU since it is the teaching model of the 21st century. The world operates based on collaboration and this is how problems are solved. No one has all the answers and all the best ideas all the time. All upper level coursework in my experience had group research projects, group presentations, group reports, etc. Some people hated it and preferred to work alone, but tough, working with others is one of the most important skills you’ll learn, and not understanding how to do it is a surefire way to ruin your career. There are competitive students at JHU who won’t go out of their way to help you or have a bad attitude (when you talk about premeds at any school you’re bound to find a few of them), so once you find out who they are just avoid them. It’s that simple. JHU is a small school and these students tend to learn quickly that they need to be nice or they’ll be picked last for the proverbial kickball game.