Vassar, Williams are mentioned for music. Brown, Amherst and Hamilton have free curricula (no distribution requirements) I believe. Other “little Iview” could be explored.
Colleges that Change Lives website is a great resource and many schools on there would be good ctcl.org. Clark, St.Olaf, others…
Bard and Oberlin are reputed to have a “low wall” between conservatory and college. Oberlin also has a Musical Studies BA- maybe someone can speak to that.
Music at a level that includes summer programs can help with admissions via a music supplement as you probably know. Some Ivies are not free for incomes under $200k and there is aid above that level as well.