You can't really have so many criteria to expect them to be ranked by, so instead i will just choose 1 of yours, "required for university courses"
In this case Chemistry is probably most important, it is the most important A level Subject for medicine and chemistry and biochem and pharmacology and all kinds of subjects. I have seen even in Biology degrees they care just as much about chem A level as Bio A level.
Next is probably physics for physics and engineering degrees, and a whole lot of anything else with technical aspects.
Finally is biology, which is mainly useful for biology degrees, and as an addition to chem for medicine.