I wouldn't talk about insurance for the biggest problem facing medicine. It's an obvious response and it's a dangerous topic. What if the interviewer then asks you the terrible "how would you fix it?" I always avoid the topic because I'm in favor of socialized health care and many many docs don't share my opinion.
So, I would say ethical issues. For example, as we make advances in science and create new technologies/drugs/etc, we are able to keep dying patients alive longer and longer... but we don't necessarily provide them with better quality of life in their last days/months. So, what's gonna happen with the euthanasia issue in the next few decades?
Obviously, you could also talk about stem cell research. How is that going to change the role of the doc? As time goes by and scientific progress is made, stem cell research will create tremendous hope and also introduce ethical concerns that we have never had to confront before. For instance, will stem cell research indirectly lead to cloning? Will scientists attempt to clone human beings to create individual designer stem cells, essentially to grow a copy of you, to be available in case you need another heart or lung or liver? And, what would the new duties of physicians be? Will they encourage the creation of designer stem cells and present them as an option to their transplant patients? Or, will they oppose it and jump back at the idea of growing spare body parts?
My positive role model, probably my undergrad research mentor... for many different reasons.
Negative role model, I have no idea... Good question! I'll think about it. 😉