You have a solid app, but literally 80% of your list is top 20.If you're going to stack your list with top 20s, you might as well do so smartly. That means looking at where your GPA falls (above or below 10th percentile) and where your MCAT falls (36-37).
The following schools have a 10th percentile GPA of 3.65 or higher. That means less than 10% of their accepted students have your GPA or lower: Harvard, Hopkins, WashU, Penn, Vanderbilt, Stanford, Yale. Their MCAT medians are all 37-38 (except Hopkins which is 36, but Hopkins has a 10th percentile GPA of above 3.7 so not a great option).
These schools have 10th percentile GPAs between 3.6 and 3.65: Chicago, Michigan, NYU, Northwestern, Sinai
As such, I might suggest removing those if you're financially limited to 15 schools and want to stack it with as many top 20s as possible. Schools that have 10th percentile at or below 3.60 are Pitt, Cornell, Columbia, Duke, Emory, Case.
Howard and Morehouse should absolutely be on your list. Pitt, Cornell, Columbia, Duke, Emory, and Case Western as well. That's 8. Mayo is super low yield, so I think that should be dropped (it's a great "add on hail mary" school when you don't have a limit because there's no secondary, but not when you're strictly limited to 15 schools. They accept fewer than 85 students TOTAL for a class of ~50. Additionally, if you're interested in health policy, you're better off at a big research institution like Columbia or Hopkins than at Mayo, which is good for getting residency at the Mayo Clinic, but doesn't have quite as much clout in the political arena). Tulane is low yield and probably not a great "safety" when you have Howard and Morehouse on there (you are like their ideal applicant).
If you want to maximize your chances at a top 20, I would recommend Northwestern, NYU, Michigan, Sinai, and then 3 less-intense schools (admissions wise) like Einstein, Rochester, UVA, USC-Keck, Hofstra.
Actually, I would absolutely include USC-Keck on there, as they fit with your career goals, like high MCATs, and are generally forgiving of "lower" GPAs. You could also, if you really want to, knock off a couple of the NW, NYU, Mich, Sinai for Harvard/Hopkins/Stanford if you really really want to (I would recommend Hopkins and then Harvard and then Stanford last - Stanford is arguably the most competitive medical school based on stats, CVs of accepted students, and acceptance rate, which is a whopping 1.9%). I would keep as many NYC schools on there as you can because they all network with each other.
So then your final list would look something like this:
1. Howard
2. Morehouse
3. Pitt
4. Cornell
5. Columbia
6. Duke
7. Emory
8. Case Western
9. USC-Keck
10. NYU
11. Michigan/Hopkins
12. Northwestern/Harvard
13. Sinai
14. Einstein
15. Hofstra
. What I mean is that I would make my list as if I had a 40 mcat score. I'm just spitballing though.
