My kid turned down merit-offers at Smith, Scripps and other LACs for UW, is happy with her choice. Now in grad school. Other kid attends Whitman with merit funds. Both ended up in the same quantitative majors, targeting the same sub area for grad school. Not bio.
Things to consider
Marching Band is an amazing experience at UW. It can define your college years.
At UW it is hard to take classes outside side of your major, except for the large intro lecture classes, usually not well-taught. (Lot’s of bad classes) That makes it hard to explore different areas if you are not sure what major you want. It can be difficult to change majors. The Honors College (highly recommend) and a few freshman seminars can help some but not the same as an LAC.
The UW honors college has merit scholarships, even full-tuition. Classes in honors college are the things professors really want to teach, so they are well-taught in small format. Students are more intellectually curious. I know the honors quant classes have a reputation for being competitive but you can avoid those & sub in something interesting like astronomy or evolutionary biology. However the honors classes serve as distribution credits and cannot be replaced by AP credits. (like most LACs)
In impacted majors at UW, the pre req courses can be brutally competitive and many students don’t get into their majors. Many majors take a few direct admit students as incoming freshman. For certain majors it is not worth the risk unless you are a direct admit.
The opportunities for research at UW are unparalleled. My UW kid did research year-round for 3 1/2 years including publishing. UW has better opportunities to build relationships with top research professors to get a better feel for what a research career is like, get mentors, help with grad school connections. Though the student has to make it happen by contacting labs, sending resume, reading their papers, asking for opportunities. At Whitman, professors asked kid if they wanted to do research.
My Whitman kid did summer research at UW one summer and Fred Hutch another summer on top of 2 years of Whitman research. At Whitman research is available but limited topics because of smaller departments.
Whitman helps students get REU’s. UW does not.
Both kids also did industry internships to see what that was like. UW had industry recruiters in contact with students all the time. Whitman doesn’t.
Whitman kid has had excellent teaching for every class. Very easy to explore different areas just for fun or to change majors. More intellectually curious classmates than UW. More focused on sending kids to grad school, fewer connections to industry. Easier to develop relationships with profs. Easier to get recs.
Both Schools have excellent bio departments.
Finally, grad school is paid for through grants, but having left over 529 $ helps with housing expenses.
I think you can have a great experience at either school. It is definitely a different experience. If she’s leaning toward UW, I say go for it. Especially with marching band.