I wouldn’t be that sure about that, especially UT Austin. The type of connections that private high schools on the East Coast have with the colleges on your reach list don’t always work with public universities, especially ones that have a very strong commitment to in-state population. While your counselor knows what he’s saying, remember that admissions to these colleges is strongly affected by policies and processes going on in the state legislatures of these states. So his advice regarding public universities in the Midwest and the Southeast may not be as good as his advice regarding private colleges in the NE and West Coast.
Also, admissions to CS at these colleges is far more competitive than admissions to other majors…
I would second a recommendation that you look at UIUC. Although admissions to CS is very competitive there as well, the do not have a preference for in-state applicants. They also have a top neuroscience institute as well.
Finally, your list of reaches is all over the place. UPenn is a very different place from Cornell, and there is very little similarity between these two and Harvey Mudd.
You should not be applying to colleges because of their “prestige” or “Eliteness”, but because they are the ones which best match who you are and what you want. Look closely at each and at your other selections, and see where you would be happy to attend.
Your list, from the safest safety to the reachiest reach should consist solely of colleges where you feel that you would be able to succeed and thrive. Nothing else is important. The least important thing in your future is what your school friends, teachers, etc, think about the college you choose to attend.
Harvard’s CS program is good, but not as good as any of the three matches you have, as well as a bunch of other colleges, like U Washington, UIUC, and more. Of the Ivies, it is Cornell, first and foremost, then perhaps Columbia, Princeton if you like theory, and UPenn if you want to add business.
Seriously - in your case, I would tell you to drop UPenn, Harvard, Princeton, and maybe Columbia. CMU is a good choice
My wife has been CS faculty for a couple of decades, is very involved in CS education, and is pretty familiar with the reputations of different colleges for undergraduate teaching. So this is close to first-hand knowledge.
While I would have, in the past, recommended that you look at Berkeley, I would not do it now, since their undergraduate program is having some serious issues of overcrowding in classes.
However, most importantly - again, what do you want, or more importantly, what do you need to succeed and thrive in college?