I think admission to USC is going to be quite difficult. The average GPA for accepted applicants this past cycle at was 3.9 and 40% of accepted students had perfect GPAs. Merit awards are incredibly competitive–only 2% of applicants applying EA received merit. The cost of attendance is also close to 90k.
For BU, the RD acceptance rate was @ 10% in 2023 so almost as difficult as USC. And it’s also-super competitive for merit. (My daughter applied last year and was accepted but didn’t get receive a penny with 4.0/4.8, 34 ACT.)
Have you considered Pitt as a target? It has an excellent reputation for science majors/pre-meds. They ranked #3 in NIH funding in 2022 so there are tons of research opportunities. There are also several hospitals within walking distance of the campus so shadowing and internships are easily accessible. (They also have a medical school.) It’s rolling admission so if you do decide to apply, make sure it’s early as that is a big advantage.
Cost for OOS is @ 55k.