Will I have a ~14.5% chance of getting accepted to Harvard? And other highly-competitive schools.

You don’t seem to have an idea of the fierce competition, including from Canada. And, what they look for. It’s not, eg, Amazon or self studying pre-calc or chem.

And Early is no special advantage if your app and supp don’t hit the mark.

Are you saying you skipped a rigorous courseload for those ECs?