First off, you have a great story. Your grades are great but really I think they’re most important to just be in the “normal” GPA range … and from there, they move to your ECs, your essay. etc.
But your biggest strength will be your story, to find ways to leverage that in your essays.
ECs in high school are irrelevant as a transfer. They only care about what you did in community college. As for anything else for ECs, just find ways to be involved on campus or in the community. It doesn’t have to be business related, just something you’re interested in and that you can hopefully somehow demonstrate impact.