I think for some people your advice is wise, but medical schools are increasingly looking for students who have a broader scope of vision to become physicians. Some of the most successful applicants to medical schools have been what I would call the outliers (after Malcolm Gladwell).
They present experiences and skill sets that catch the attention of medical schools admissions readers. It is those willing to take academic risks and succeed in doing so who are the ones they most want to enroll. Or at least this is my experience of working with students. I have written a number of recommendations for medical school and the ones I enjoy writing for the most are the ones who have taken the road less traveled and judging by the acceptances these students get I think some top medical schools would agree.
But it is a more challenging road. That is why it is less traveled but also why it is more memorable than the standard premed applicant.
I don't think there is a template that works for every student. I advise students to develop their passion to the highest level, whatever it is, and if it is exceptional it will help develop them as people and the other stuff (getting into grad school or a great job) is just the extra that might occur. I think the education of the person takes precedence over the focus on acceptance and I think many people who evaluate students would agree. Or at least this is what I have been told, but this is simply my experience and you might be right.