Mezzomom: The bus schedule is OK, but not always great. Classes at the 2 campuses are offset by a half an hour. I think River Campus classes start on the hour and Eastman on the half hour. Theoretically, if you have an 8:30 class at Eastman, you are done by 9:20 and can get the bus in time for a 10:00 class at River Campus. Son had that type of schedule once and says it was not unusual for him to be late for his River Campus class. This past semester they did institute a quick shuttle in the afternoon that runs from River Campus straight to Eastman with no stops in between. He says that has been very helpful.
He has never been discouraged from taking classes outside of Eastman. His teacher is very supportive. The private teacher is really the most important factor. I know there are some teachers who feel that students need to spend all their time on music and discourage students from taking outside classes. Your daughter would need to talk to her perspective teacher to find out how they feel about taking outside classes.
The biggest factor with taking outside classes is time. Not just the travel time between the 2 campuses but time in general. I think this is going to be true no matter where a music student attends. Eastman requires 18 credits for freshman 1st semester and 17 second. (Students have more flexibility if they can test out of piano.) The classes along with ensemble rehearsals, master classes, lessons, and several hours of practice each day doesn't leave time for much else. Son seriously thought about a double degree but decided that he really couldn't cut sleep out of his schedule
He is taking a minor in political science instead, which is very doable.
If you have other questions regarding Eastman, I will be happy to answer them.