Typically top 15 b-school grads exit into industry roles at “manager” level, but oftentimes, you will be managing processes vs. people. The people management will follow shortly, after demonstrated leadership. Given your goal, I would recommend that you aim for top ~20ish school, as I typically see exits from schools outside that range at Senior Analyst level. From my experience, the difference between top 5 and top 15 for industry exit is very minimal, usually it comes down to the company/industry choices.
Although you probably won’t be working 90 hours a week, the expectation on hours would be greater than 40, depending on the organization.