OP, as a junior, he has plenty of time to fine tune his ECs, add breadth, show a willingness to try more. Top colleges want kids who can climb out of their usual comfort zones. They look for evidence.
The phrase is “Show, not just tell.” So, not IF I get into your college, here’s what I’ll do. Instead, they look at what you DID do, as an indication of what energies and openness. Maybe he could do theater now and in fall. Even tech staff is good. He can pick up community service that’s not just JROTC, but works with community needs, those needy, has some impact beyond JROTC. And more. He should work in politics now, find the context he IS comfortable in, not stop short.
One thing breadth does represent to top tiers is awareness of more one can do. And then choosing to do that. It needs to be relevant to the colleges, college life. Not just his interest in libraries, eg.
NHS varies so much by hs that it’s not really a major tip.
I’m sorry, but from my perspective, his primary (nearly solo) EC is JROTC. Even extras like tutoring or what else are through that group. He needs to expand. And he should be able to get ideas on his own. We all help our kids, but ultimately, it’s their responsibility to narrow down, discover additional interests.
For that reason, I think others would agree his college targets are not about your fears of CA driving. Most college kids aren’t joyriding the CA cliffsides. Many focus on campus and the local towns. I spent time at UCLA and we barely drove further than Malibu, for a dinner. My friends drove carefully.
I was on Rt 1 a year ago and surprised how, further north, on the coastal highway, there are lots of places with no guard rails. But he’s going to college to study, make friends, not tour the coast.
Think about it.