Congrats on getting in to these great schools. Since they are all top notch and will provide equally excellent educational experiences, it really depends on what you want to do in the next 2-5 years.
Hopkins is a fantastic school, very short program so you can get in and out (if that's what you want). The city is lovely, people may warn you of safety concerns but the medical campus is really secure. The city as a whole has been through some positive changes over the past few years. Great place to live and friendly people, although nothing compared to Boston or NYC. Program wise, it's fantastic, and you'll find yourself at home with a majority of medical practitioners in the MPH program (and tons from overseas). It's an inspiring place to be, and you can meet some equally inspiring people. I generally found that faculty were friendly and accessible. Close to DC, so a lot of faculty do policy work as well. Career-wise for your husband, what's his field? Like you said, might be an issue. But DC is close by train, so that's also an option. And again, you'll be out in 11 months. Most people don't really stay in Baltimore unless they want to stick with the academic or research side. Most will relocate to other cities on the east coast like Boston or NYC, or move to DC for policy or NGO work. So in that sense, Harvard or Columbia may be better for you.
I cannot speak to the Harvard or Columbia programs, but I think Harvard will have equally large number of medical practitioners in the MPH program (if not the majority, unless they changed the admission requirements), whereas Columbia will have less. That's neither good nor bad, since you may get the chance to meet people from different fields with different training.
Since your husband may find better opportunities in Boston or NYC (plus more income to carry the weight for these expensive programs), I would lean towards those schools, unless you had a specific reason for wanting to go to Hopkins (eg faculty, research). Reputation wise, I'm not sure there's a practical distinction between graduating from Harvard versus Hopkins. Your husband's quality of life is important too, and I think you should consider those factors, especially when the options are equally great. Again, it really depends what you want to do in the next few years, where you want to work, if you want to work with specific faculty or research programs, etc.
Also, if I were you, I would also ask the admissions office for student contacts and also seek out your own contacts via LinkedIn - see if you can get them on the phone or Skype for an informational interview and ask about their experiences and satisfaction with the program, quality of life, cost of living, career opportunities, etc.