Which schedule for junior year would be better?

Stick with schedule B. While grades are important, they're not the only thing that colleges take into account and in school or out of school extra curricular activities are a must for NYU or any other college really. Plus, the AP classes are also core subjects, which colleges prize and you need time off to deal with homework and other activities. Besides too many AP classes, not only bring your GPA down but can hurt your overall chances at a college as someone who does everything but is not spectacular at anything. Like a jack of all trades but master of none type.