I agree that pedigree is important in I-banking. But, perhaps not always Ivy level, necessarily. Ideally, you'd do an internship in NYC at one of the large firms. Hopefully you impress them enough to be granted an interview post-graduation. Then, yes, as you stated, these guys work crazy hours doing analytical work and working on proposals/presentations and putting together an analysis on a particular project. 80 hrs is not unusual.
Then, if you want to go anywhere higher, you'll need an MBA, and from a reputable institution, because very often your clients expect that if they're to take such "young" people seriously. Sure, you can make money, but if you can't imagine enjoying the I-bankers life (i.e. the day to day functions of the job) and living in a large urban area, then I'd seriously hesitate to even think about it.
I have a cousin that was just made a VP at one of the big players on Wall Street. He now makes some great cash (min 350-500k) and will be 33 this September.
Personally, I could never see enjoying law, or I-banking....... However, I'm super happy for my cuz.