Not just extremes in what he swallowed: he’s notorious for “La Comédie Humaine” [0] his dozens of novels are actually set in the same fictional world, with consistent characters across decades. You can take excerpts from several books to tell a completely original story. It’s the most detailed world ever described —from individual thoughts to gruesome details about poverty, up to overarching consequences of the industrial revolution on the remaining aristocracy.

[0]: https://en.wikipedia.org/wiki/La_Com%C3%A9die_humaine

That sounds a lot like the basic idea behind Terry Pratchett's Discworld.

It is, although more XIXth-Century realism, so darker: someone who was drinking at a bar reappears as a ruined alcoholic later. Someone who got rich suddenly turned mean.

A lot of the speculation on the forty-something unfinished books are based on those trajectories.