Did you get into the honors college anywhere else?
If you didn’t, I’d pick UMass for Commonwealth Honors. The opportunities you’ll get and the quality of experience will be better - smaller classes where you get to know your professor, priority registration (this alone is worth its weigh in gold), excellent dorms, the “commonwealth campus”… in addition, with the 5 college system, you can take classes at elite colleges like Amherst, Smith, and Mount Holyoke.
Stony Brook is indeed strong in the sciences, but for an international student it can be very lonely because it’s a commuter campus, with many students leaving at night and most of them leaving over the weekend, hence reducing the opportunities to socialize and network, and reducing the need for the university to provide entertainment, means international students are on their own instead of having free activities provided on campus. I think Stony Brook would be a good choice for a grad student who’s already settled in the country, but not for a freshman.
UWashington is better than either one but it’s indeed too expensive to be worth the cost differential.
If you got into Honors College at Stony Brook, ask whether there’s an Honors Dorm and how many kids live there over the weekend.