Maths is useful when you get to medical school. DD found that classmates without it struggled with some of the first year content.
It is worth having 2 STEM/lab science A levels, including chemistry. Then it depends on the student. Dyslexic DD found biology the hardest, but others will find it the easiest. Relatively few take physics, but if a student is maths/physics oriented and less than 100% sure that they want to study medicine, it keeps engineering type doors open. It is also useful if radiology is a potential direction.
DD was able to take five, so 3 sciences, maths and electronics. If she had had to narrow it down, she would have chosen maths physics and chemistry. Engineering was her fallback, what she chose to study as her intercalation and where the physics and electronics really helped. A school friend, who was an exceptional mathematician, opted to intercalate in epidemiology. Medicine has a broad range of careers and so there is advantage in keeping up subjects where you are naturally strong or have an interest. This board is focussed on actually getting in to medical school, but it is worth keeping an eye on longer term ambitions, as long as they fit most medical school criteria. A student will probably get better grades in subjects they enjoy.
Note: being an academic high flier is not an advantage when applying for medicine. Neither DD nor her friend did particularly well in the application process with DD only getting an offer late in the process and her friend having to take a gap year to reapply. However once in, strong academics makes life easier.
I agree about PE. DD took a sport to a high level and so had access to physio and nutrition advice which is what sparked her interest in medicine. IT (whatever the subject is now called) might also be a good one if there were an interest in academic medicine. Regardless of career, an ability to code and to handle data will increasingly be an advantage. .