Congrats on the scholarship!
I don't know if you've really looked into Pitt law because of how good your stats are, but do you know how competitive the JD/Carnegie Mellon degree program is in terms of admissions? Also, what is the relationship like between Pitt and CMU?
Unfortunately I don't know much about the JD/CMU degree program, sorry. As far as the relationship between Pitt and CMU -- I'd say it's fairly strong. The two schools are extremely close to each other, so it's very easy to traverse back and forth. At the UG level, Pitt students can take CMU courses for credit. More anecdotally, CMU is very tech and science oriented and everything about the school reflects that. The students have a reputation for being a bit hard-core and socially awkward, and I have found that this stereotype is generally (although not always) true. For this reason, I feel as though I sometimes do not hear much about CMU despite the fact that it is less than a ten minute walk from campus. That is also undoubtedly in part because I don't actively seek out CMU campus news and events and the like.
One thing that is nice about having two college campuses so close to each other is that the entire neighborhood feels young and vibrant. Parts are a bit grimy, but there are plenty of coffee shops/places to eat/stores/etc.