SF and NYC are definitely the centers of your industries. NYC has been like a parody of itself for the past decade or so, in my view, and you know how SF is viewed. But, if you're looking to "make it", you will almost certainly work for a company in one of those places. Right now you can maybe get away without living there, though. That may or may not be what you want. Personally, I wouldn't live in either of those cities, though I would have when I was 25, though they were also different cities then.
The three suggestions you put there sound good to me insofar as they're "second-tier" cities, which IMO is a good thing despite the pejorative nature of the term, because they're less likely to have totally jumped the shark the way NYC and SF (and London, and Berlin, and...) have. I can't comment in detail because I've spent limited time in them, but my only advice would be - despite the fact that you're not looking to settle down - to try to get a job (and salary) from a NYC/SF tech/finance firm, but live in one of those cheaper and a little more down-to-earth (relatively speaking) places, where I think you'll meet higher caliber people with better potential for long-term reliable friends, lovers, etc.