But I don't think those jobs exist unless you're already an expert in something and can get by on the expertise that you already have. Please prove me wrong!

For your example combination, I've known entrepreneurs who've met that mark, but it took some initial risk taking and sacrifice. The work isn't sexy by most SV measures but they make extremely good money and one in particular takes months off every year to travel in Europe while in his 30s. I wouldn't call them an 'expert', they just found a niche that other people didn't find interesting enough to pursue.

Likewise, for other combinations (say 'interesting work + high pay') you may have to put in early work for a PhD where you aren't getting paid well initially. For other combinations ('work-life-balance + interesting work') I've known people who essentially worked for free in order to network and prove themselves until they were offered one of those positions.

I guess the point I'm making is that those desirable combinations don't naturally just fall into the laps of most of us but are the product of deliberate and conscience up-front work that can't necessarily be templated out.

I don't think most civil servants qualify for the high pay portion (at least by comparison to SV pay scales), as their pay is capped. And work as a contractor brings about a host of other issues

The academia route certainly exists, but the glut of of PhDs compared to available positions combined with the amount of complaining I've heard from non-tenured professors would make me a bit hesitant to advocate this route as a general recommendation. But there are other staff positions that might better fit that bill