For me, Id say higher ranking school. Im interested in going into Academia too so ranking matters to me, as well. There are a couple of schools that are high ranking but still have a good amount of POCs. UChicago for example, has probably one of the highest percentages of minority students (URMs) for a medical school despite it's small class. UMich, some of the UC schools, UPenn, also seemed to have a diverse student body and a sizeable african American community. For me, I feel like HBCUs are just like PWIs in the sense that they don't have as much diversity as I would like (someone please check me on this if it's not true). I've grown to enjoy being around people who are not my skin tone or ethnic background so going to an HBCU seems counter to my goals and interests. Just my two cents.