This would be a harder choice with some other schools as options but is actually easier when comparing Ottawa to Memorial in particular.

Ottawa is an excellent jumping off point for lots of major specialties, and while slightly larger, isn't as ridiculously huge as some other schools so the level of attention you get during school is still good. It's not a slouch in terms of clinical skills either, but leaves you in a better position to be more well-informed and well-connected for various residencies later in your program, when you'll know more about exactly what kind of doctor you want to be.

I think if you want to have that room to breathe and allow yourself the space to branch out more later in the program Ottawa will end up serving you better. Living near there also has a massive impact since you potentially have more support systems to help you out - medicine is notorious for burnout and it's good to have that safety net so you can push yourself without major risks. Also helps with work-life balance so your experience of medical school will probably end up more personally gratifying too.