I don't know how it works in the humanities, but on the sciences, in the different tiers @RevolverRob describes, you're will be a definite difference in how much time someone spends on the subject matter. Big professors that run big labs spend a lot less time with the science and a lot more time with the politics of university standing and grant applications. "How much time do you spend doing the stuff you like" is a legitimate question as she researches her options.

Regardless, congrats @JohnO , sounds like a great kid. Good job.