Improving my app

GPA(weighted)- 4.8
Unweighted- 3.85
Rank- 11/437
SAT- 2110
ACT-32- I’ll take it again
EC- Cheerleading (won state)
Diving
Track
Junior exec (planned prom)
Dance Marathon Morale dance member for Riley’s children hospital
Student Renaissance member
Math team and Fine Arts team member (Academic Super Bowl)
Currently running for SC president
I also just got my pilot’s license, so that’s unique I guess?
AP psych-5
AP macro-5
Ap chem, AP bio, AP Lang-?

I’m currently a junior, and I plan on applying to several ivy and top tier schools next year- Stanford, Dartmouth, notre dame, Yale, Princeton, USC, UC Berkeley etc. I was wondering if anyone had any advice on how to improve my application. I really wanted to take a college course this summer like computer science or physics, but the schedule conflicts with cheer and diving practice. I want to learn computer science because I could see it as a potential major of mine, but I think my only option is to self study for the AP exam due to my busy schedule. Is there anything that I could do this summer to really make me stand out? I know my test scores are pretty low, but I’m fairly confident that I can improve my ACT to a 34 or above. My SAT score is stuck because I have taken the test 3 times, and Stanford does not practice score choice, so I hope the schools will forgive my SAT score if I have a better ACT score (wishful thinking I know). If I wrote about flying airplanes in one of my essays, is there any possible way for that piece of writing not to be terrible? I’m not bad at writing I just can’t picture incorporating flying into any of the Stanford essay prompts.
What should I do over the summer to make me look good? I like STEM subjects a lot and flying airplanes and doing flips on the ground and doing flips into the water. So anything that combines all of those things would be ideal, or just something academic. All advice welcome, criticism too I guess.

P.S. Stanford is my dream school