What advice would you give to students who aspire to study physics at the PhD level? Do you think there is an oversupply of PhDs? Do you feel a conflict between pursuing what you like and being realistic (about getting a job)?
A PhD is a really nice thing if you enjoy doing physics. But don't walk into it blindly. Some people pursue a PhD in astronomy, get one and can't find a job otherwise because their PhD did not prepare them for anything aside from academic research. And academic research is quite difficult to get into, there are more people wanting to do it than available spots.
So be smart and try to obtain some marketable skills during your education. I am talking about programming, engineering, numerical stuff, internships, etc. Going for a PhD is certainly possible while in the meanwhile making sure that you won't end up in McDonalds with your PhD (yes, there have been stories of mathematics PhD's ending up making sandwiches in subway).