Which path should I take, if we were to put aside costs for a second, if I wanted to increase my chances of being accepted into a college that is offered by Questbridge and has an early action program, like Columbia?
I’m not 100% sure but I think Questbridge is a much better deal. Also if you don’t make columbia you can fall back on the other 9 you can sign up with QB
Columbia offers binding Early Decision, not non-binding Early Action, for frosh admission.
Questbridge is like applying Early Decision to multiple colleges ranked by your preference (so, if any admit you, you get the letter from your highest ranked one and are committed to attend it), so it is advantageous to use Questbridge over a single college’s Early Decision program.