Thanks for circling back to let us know what you’re thinking!
Please make sure that you would be happy to attend any college on your list. Although you may well get multiple acceptances from schools with low admit rates, there are no guarantees. That said, you’ve got some great schools on your list that I would be shocked if you were not admitted to (i.e. most of the publics outside of Cal, though make sure to submit Pitt’s application early).
I’m assuming that when you mentioned Washington that you’re referring to Washington University in St. Louis, aka WashU. If so, you may not know that they just announced that they will be offering an EA round ( WashU in St. Louis Admissions Updates for Fall 2027 ). It’s not known how WashU will be treating the EA round (part of the discussion in the linked thread), but at some schools it is very different to get in RD. Essentially, if one wants an acceptance one needs to apply EA or ED. Since you indicated that you really appreciated the interdisciplinary flexibility at Northwestern, that seems like something that would appeal at WashU, and thus may play a factor in whether to REA at Stanford. You may also see if the new WashU EA is required for scholarship consideration in which case an application EA there would be allowed under Stanford’s REA rules (source).
As college acceptances roll in, I would investigate those schools further. Follow the school’s social media, the clubs that you’d be interested in, the different dorm options and LLCs, etc. Possibly create 4-year course plans that would meet the school’s distribution requirements, your major requirements, etc. (Some people find doing that activity can be very illuminating and sway their opinion about a school, whether positively or negatively.) Doing all of that will help you to weather the wait until your most selective colleges respond, as that wait can feel interminable. It will also (likely) make you more excited about the options you currently have, which can help to blunt the impact of any rejections you may subsequently receive. And it will be a more efficient use of time to examine each school that has accepted you as the acceptances roll in rather than waiting until April 1 to further research all your acceptances and winnow down to your final selection.
The only other advice I would offer is to take care of yourself physically, mentally, and emotionally. Your value is innate to yourself; it has nothing to do with which colleges grant you an acceptance. And from what you’ve done in high school, I think you have a very bright future ahead of you, no matter where you land.