Overall I agree with some of the later advice you’ve been getting - aiming for Ivies + Stanford and MIT is putting all your eggs in one basket. I think you’d be a strong applicant, given your test scores and background, but these places all have < 10% admissions rates and adding some schools that are at least in the 30-40% range would be a great idea. The first one that came to mind is Brandeis, and there’s also Boston College, Wake Forest, Case Western, Lehigh, Tulane, Boston U, many others. There are many schools that are sort of forgotten in the middle - schools that aren’t quite as competitive at HYPS+ but offer an excellent education and great access to post-college opportunities, including top law schools.
Columbia does take legacy status into account, but it doesn’t have a huge impact.
We are always pleased to receive applications from students whose family members have graduated from Columbia. When an applicant is extremely competitive and compares favorably with other similarly talented candidates, being the daughter or son of a Columbia University graduate (from any Columbia school or college) may be a slight advantage in the admission process. This advantage may especially apply for “legacy” candidates.
Normally Columbia College does not accept students who have taken a break from education of more than a year; however, they make an exception for those who completed mandatory military service. When there, I met several students there who were Israeli and had done their mandatory service and were still in CC (and one other student who was older because he took two years to do a Mormon mission).
I’m not sure what the chances are, but if you are really trying to leverage that you could instead apply to the School of General Studies - it’s tailored for non-traditional students; many of them are prior military; the acceptance rate is way higher than the CC acceptance rate (I think around 26%) but you would take all the same classes and could participate in all the same activities as a CC student. Since college is just a stepping stone for you, it kind of wouldn’t matter which division you attend in.