These are all very good universities.
I am not a big fan of applying ED unless two things are both true: (1) The university that you apply ED to is clearly your top choice; (2) Either you are fine with being full pay or the NPC shows the school as likely to be affordable for you.
The fact that you are not sure which university to apply to ED makes me wonder about the first issue. Which of these schools would you rather attend? I will admit that for the two that I am most familiar with I would have trouble deciding between them.
This is very difficult to judge. To me it looks like your grades are good enough for admissions to think that you could handle any of these three schools. Your SAT is superb. Two B+'s are not all that bad, but junior year is an unfortunately time for this to occur. Highly ranked schools in the US, including these three, get way more qualified applicants than they have places for incoming freshman. They are all reaches.
Mostly I think that you need to make sure that you are applying to solid safeties and that you are happy with your safeties. You also need to make sure that your budget fits the schools that you are applying to. For someone who majors in public health a master’s degree is not completely out of question, and you might want to think about whether this would fit your budget. You can do well in public health with a bachelor’s degree from a school that is not ranked in the top 50, or even in the top 100.
Do you have a specific career in mind?