You're certainly not aiming too high. You should at least get into Yale, BC, and PTS. From what I understand, however, Notre Dame is extremely hard to get into, and receiving significant financial aid is next to impossible.
Have you considered the Toronto School of Theology? It's probably the best theological consortium in North America/Canada, and it would be a great fit for someone who's ecumenically inclined. I'm going to apply to TST's Wycliffe College ("Yale north," as it's often called), as well as to Duke Div, Perkins School of Theology, and Princeton Theological Seminary.
I share your skepticism about Harvard and Chicago being able to demarcate a particularly orthodox Christianity. That might not be a huge factor for a doctoral student, but for someone pursuing an MDiv, the schools you've selected are certainly great options.