The legacy will be some help. But once you are in the high gpa and test score area it will come down to your letters of recommendation and your ECs and personal statement. In your post you make no compelling points for admission excepting the legacy tip.
fyi there are college specific forums you can ask your question in but ‘chances’ isn’t welcome in specific college forums. Asking for data is fine. But unless the college releases it, or unless the Crimson polls it that data is not available.