All great choices - can’t go wrong with any of them in terms of reputation and quality. Austin has a great vibe, especially if you’re into the indie music scene, and also a great place for tech startups, but beyond Austin, Texas is … Texas. (Yes, it’s hot in the summer but you might not be there during summers anyway.) Weather aside, Michigan is probably the nicest overall in terms of nature if that’s important to you.
Since you’re Californian why not take the opportunity to experience another part of the country, broaden your network, etc.