Ask HN: How good of a developer were you in your 20s?
Are you satified of what you have become?
More seriously, the biggest question I have looking back is what I expect many have: was I correct remaining a big fish in a small pond or should I have gone general, moved to Mass or California and help extend Unix. Hacking was the key. No management and no concern for big bucks, just enough to keep doing what I wanted to do.
On the whole, it worked out ok.