The math and economics departments at Mount Holyoke are excellent. A large number of students in both fields go on to competitive jobs in banking. Several of my peers in those field graduated with six-figure salary job offers... that alone should speak to how great the training is on campus, and to its reputation. The best thing is that if you don't think the courses on campus are enough to give you the background you want, you can always cross-register with one of the other four schools in the consortium. Needless to say, you have some excellent offers - and I'm sure you'll make a great choice, no matter what. When I was a student (2 years ago now...), there was a big issue with the econ department because there weren't a lot of professors, but there were a lot of majors. I believe that has since changed... one of the greatest benefits of the consortium is that UMass sometimes allows you to register for graduate courses, which benefits you in the long run.
Don't just think about what you want academically. Think about what you want socially from a school. Smith, MHC, and Wellesley are all women's colleges, but each is very different (though not so to the naked eye). It goes without saying that GW and UF are nothing like any of these three schools. Go where you think you'll be happiest. You end up where you're supposed to end up... and if you don't, you'll have the opportunity to transfer. Good luck!