Chemistry, Biology, and Maths without a fourth option are sufficient. Another subject is unlikely to benefit regardless of whether it's Physics, Further Maths, or something else. Reviewing some physics topics from GCSE/AS level might be helpful for e.g. physiology labs and stuff - notably stuff on electromagnetism and circuits if you don't take Physics.
They aren't going to see you've taken Latin and say "ooh they've done something different we definitely want to take them". Additionally getting A*AAA rather than the required A*A*A will immediately disqualify you regardless of subject choices (from Oxbridge specifically, that is). There's really no benefit to doing a fourth subject and not focusing on your core subjects.
Even if you're not wholly committed to medicine, Bio/Chem/Maths will suffice for entry to pretty much all bioscience and chemistry courses, as well as perhaps a small number of engineering or CS courses (in e.g. Materials or Chemical Engineering), Law or Economics, and anything else which doesn't have specific subject prerequisites.