I’m sorry you had such a tough time last year. You’re obviously very bright and motivated; there will be many good options for you to do well in college. Most likely, a 3.5 unweighted with a downward trend is going to take the most highly selective schools that expect a high level of consistency (both over time and across subjects) off the table. (Not to say you shouldn’t apply to a few, but the odds aren’t great.) But you sound like you’re aiming for a pretty realistic range of schools, and there are great schools that are realistic for you!
My first thought was already mentioned above: RPI. Rensselaer is a highly rigorous, STEM-focused school that is every bit as strong in your areas of interest as the super-elites. Their undergrad population is only 31% female and they are always trying to improve that. It’s not a school for the faint of heart, rigor-wise, but clearly you’re fine with rigor on the STEM side of things, and you don’t sound like someone who might change her mind and become a humanities/social science major! It’s a great school for CS and/or Physics. I feel like they’d be very happy to accept an applicant like you with a STEM-tilted record.
Rose-Hulman is another in this vein (if the rural Indiana setting works for you), and Colorado School of Mines is another, particularly if the outdoorsy Rocky Mountain setting would be to your liking. (Lots of great traditions, like this for example: School of Mines students are floating (and capsizing) cardboard boats on Clear Creek - YouTube ) There’s also Stevens in New Jersey, right across the river from NYC, and WPI in Massachusetts, and RIT in Upstate NY.
The other approach is just to aim for flagship public U’s that are strong across the board and in your areas of interest in particular, but not insanely selective. Plenty of opportunities to be the cream the rises to the top at such schools. That seems to be the route you’re taking with your current list. Worthy additions to that list would include U of Minnesota, U of Colorado, and U of Utah - all very strong in your areas of interest, and Utah has the advantage of allowing students to gain residency after the first year, which can save a lot of $ in years 2-4. Pitt would be a great one to throw in as well - their admissions are rolling, so you could apply in August and hopefully get an early acceptance under your belt in the fall.
I agree with others that you could also have admission success at LAC’s, but these may have more of an emphasis in the humanities and social sciences, once you’re there, than you would prefer; and you might find yourself in the minority as a STEM-focused student. Would you rather hang out with other CS/Physics/Engineering-loving students, or would you be happy having a lot of more liberal-artsy friends? What you prefer socially is a big factor here.
Lehigh could be worth a look - if you’re Asian, as people have suggested upthread, you’d be considered URM there. They have very strong STEM but also other areas of strength, and a more traditional social scene with a lot of Greek participation.
The UK/Netherlands idea is interesting too, if you’re comfortable going overseas.
If you look at the above schools and give feedback about what does and doesn’t appeal to you, that will help to refine the suggestions you get. Hope you’re getting some time to de-stress this summer, too!