I'd have acted on my (relatively low-effort) ideas that turned out to be profitable when others actually did follow through.

I do wish things had conspired so that I was a little later in the evolution of web development rather than the very beginning -- there's a big difference between 1992 and 1998.

I became a dev in (at least how I saw it) the age of breadth being more valuable than depth.

Now it seems that we are shifting to depth being (much) more valuable than breadth. So, I think I’d focus on becoming an expert in something instead of being a generalist.

With time, resources, and money, I'd get a masters. If money allowed me to live better than a ph.d student life, I'd strongly consider it.

Start my own business earlier.