Fascinating. We may have worked for the same founders at some point, as I have had nearly the exact same experience (I was an engineer at the 2nd startup with a ~0.5% stake (before dilution, of course!) -- the payout was nice but it was not a life changing event).

One detail in my story is that I found out a lot about the personal lives of the founders and their friends. They all came from obscene wealth to begin with. The founders father was on the board of a major tech company in the Bay that bought the first startup and financially backed the second.

The nepotism I've seen in my career disenchanted me long, long ago.