First off, BIG congrats to you! That's awesome that you're getting that sort of financial assistance regardless of what you decide.
For me, Ross and Tuck are pretty much at the same level but really two different programs (size, method, etc.). I would take the money out of the picture for just a minute and REALLY research the programs, the academics, career services, etc. It has to be a good fit with you and what you're hoping to do. Tuck and Ross will both get your foot in the door with consulting firms -- in the end it's up to how you do when those opportunities come so I don't think you're gonna get short-changed by one school over the other in that regard.
I'd dig into the curriculum...see what courses, electives, special programs, etc. really peak your interest and go with that. Best of luck with your decision but just be grateful that you have such good options on your plate!