If you don't mind them being mixed with CA cichlids from other parts of Central America, I recommend thorichthys helleri, aureus, or the mixteco varieties if your tank is at least a 75. Medium sized live bearers like sword tails, mollies, and other xiphophorus species would work well. You can also use medium deeper bodied tetras that are more robust like Bueno's Aires tetras or Columbia tetras if you don't mind venturing into south America. The Buenos Aires tetras actually closely mimic the CA native Astyanax tetras while not growing quite as large.
Decorate with sand and some round boulders. Add some wood to create more shelter and plant with a few pieces or hornwort and some lilies and you can have a gorgeous tank.