Sorry to be so blunt, but your plan makes very little sense. If your goal is to get into med school or pharmacy, then do a science undergrad. This would be a much more logical route to a career in healthcare, of course. It also seems to be more in line with your interests (although, based on your post, I fear that your interest may actually be in a career associated with money and prestige, as opposed to law or med per se, but maybe I am wrong).
In any event, and in case you haven't heard, it's actually quite difficult to achieve high grades in law. In addition to the shear volume, the material is very dense. Moreover, all of your classes will be graded on a curve and, generally speaking, your classmates will be coming from high achieving backgrounds.
Final exams (which count for between 75%-100% of your final grade in a given course) are generally open book and consist of essays / short answer type questions. The exams require you to spot issues in hypothetical fact pattern(s) and apply the applicable law to solve them. There is very little rote memorization. Sometimes an entire exam will be based on your analysis of a single fact pattern. The margin for error is slim. Depending on the curve, a wrong answer on a single sub-question can drop your final grade by a whole letter. I would note that some professors teaching pure civil law classes (e.g.,obligations, property) tend to give exams wherein students are expected to give very pointed answers (e.g. regurgitate a given article of the Quebec Civil Code) . This makes the game less "subjective" as you say, but again, the material is not always easy to grasp and apply. You'll rarely if ever feel confident with all of the material covered in a given course.
The result is that grades are very difficult to predict. It can feel like a crapshoot at times. You can attend every lecture in a given class and study your ass off for the final and still end up with a disappointing grade.
In my view, law is certainly not the program for you if your goal is simply to earn high grades and ultimately transfer to med school/pharma. Do a science undergrad if this is where your true interests lie. If you do well enough to transfer into med, great. If not, law school will always be there.
Overall, law school is not something I suggest you jump into unless you're seriously committed to becoming a lawyer. It can be incredibility stimulating and enjoyable, but make no mistake, it's a long, hard road.