ECs living outside the US

I’m an Asian female and US citizen living outside the US. Therefore, several EC opportunities are unavailable to me in comparison to domestic residents, for example my country doesn’t allow high school students to intern or do research in labs. I’m also barred from participating in national and international Olympiads because I can’t take the qualifying exams due to the fact that I live outside the US.
I don’t want to make this sound like a list of litanies, but I’m rather concerned about how my application will be viewed in the light of the ECs of other applicants. I have however tried my best to make use of the opportunities available to me. I’m a prospective physics and astronomy major, so I believe that Olympiads and internships are the most common ways to create a ‘spike’. Nonetheless, here are a few of my ECs:
Carnatic violin (nine years)- there’s no concept of orchestra in this style of violin, but I have performed solo at concerts
Started an initiative involving 75 students which does a variety of volunteering activities- not sure how this will be viewed because we are not a formal organisation
Student data analyst with the Green Bank Observatory (online)
Attended an undergraduate-level lecture series on astrophysical phenomena at which I was the only high-school student, however this doesn’t count for college credit
Cofounded a small business that donates 70% of proceeds to charity- this is a registered business
Founder and president of physics club at my school
I’ve conducted variety of physics and astronomy outreach projects with younger students and underprivileged students (this is rather minor)

My grades (CIE A levels) and test scores are high. In the context of ECs- let’s disregard essays at the moment, I’m working hard on those- would I be competitive for top colleges in the US? Is there anything I should work on or omit?

Take a deep breath. Your ECs look pretty darn good to me. I wouldn’t stress so much. Your ECs will be compared in the context of your local situation. They will understand that an international expat US citizen will not have as many opportunities as a US based student.