> I found the self-aggrandization on the part of the author to be somewhat grating, to the point I'd not want to invest the time reading through it to get the insights.
My retrospective is that the author just uses his (and others') experiences as examples. But he discusses both his highs and his lows in the book, and as such it really didn't rub me the wrong way at all. Maybe it depends on personal preference (or how inspiring you find the actual content), hard to say.
> I've also heard the stoics are quite good
Maybe that's a path to happiness, but I found the following point of TSAoNGAF to be incredibly enlightening (and, retrospectively, fully in line with my experiences thus far): Happiness stems from the act of overcoming challenges. It is expressly not some state you eventually reach, but a transient in the process of getting somewhere you want to be. Probably the main takeaway from the entire book for me is that the single most important thing for achieving happiness is choosing what problems you are going to deal with day to day. (That's also the deeper point behind the title: Choosing what to give and what not to give a fuck about.) The idea of finding the right mental framing for the world around you instead of letting it rule your emotions is the same as e.g. the parable you mentioned or the stoics (I guess).
Ok, enough of my rambling. If you do read the book (I'm not set on changing your mind) I'd be happy to hear your thoughts on it, and maybe even how the ideas within compare to the ones from Taoism or Stoicism. I'll keep my mind open to the sources you suggested too. :)
