ECs for prospective undergrad physics major currently studying in India

I’m a current junior studying the CIE A levels in India. I’m planning to apply to UCSB, UC Berkeley, and UCSD along with Princeton, Caltech and Cornell as reach schools and U of Arizona and U of Washington as safeties as a prospective physics major. My grades and test scores are pretty strong, but I believe I lack in the extracurriculars. My school doesn’t have clubs that quite interest me, nor do I have any work experience (working pre-college is culturally unpopular here in India).

These are my current ECs:
I do astronomy activities with my school’s junior science club for two hours each week
I’ve been learning Carnatic violin for eight years, however I haven’t taken noteworthy exams
I’ve founded an initiative with 75 volunteers over two cities and we’ve done a variety of volunteering activities for over a year
I analyse pulsar plots as a member of the pulsar search collaboratory, but this isn’t a selective program

Prospective future ECs:
I’ll be doing a physics or CS related internship which I hope will lead to research opportunity
I plan to start a physics club at school

Any feedback about how strong my ECs are and what else I could do would be much appreciated; thanks.