Improving Quant Background

A lot of people are interested in improving certain skills before B school, including quant. My recommendation is usually to do what you feel will help you the most, forgetting about the impact this will have on your application. This is not to say that adcoms don't care, because they do. BUT, they only care a little bit overall, as these extension courses are not that impressive regardless of where they are taken. A real class in person will look better than an online one, and of course the better the school, the better it looks.

In terms of what to take, Stats will be much more relevant than Calculus. That said, only do this after you have mastered the GMAT. I would rather see you score 20 points higher on the GMAT and forget about taking any class. Often people spend too much time taking these classes and forgetting about the core of the application. The same argument applies to your essays. If your essays are not perfect (with or without guidance), work on that first and if you don't think you have enough time to do everything, the class should absolutely come last. If you can do it all, go for it, I just want you to spend your time wisely.

Good luck!

Scott Edinburgh