Fairfax Financial would be my pick (and is also my largest single position)

Hmmm, I've never felt entirely comfortable with them. A bit too close to financial engineering, and a bit to keen on large macro bets, leading to multi-year stretches that look great or terrible. More hat than horse.

My first thought for the criteria I mentioned is Loews (L). They have had some hits and some misses since I first owned some in 2010, and it was certainly a very bad place to have your money between the credit crunch and the pandemic compared to a random big firm, but they always seemed rational and trustworthy. They do seem more comfortable in the oil and gas realm than I; I always do poorly there.

Right now I'm reading up on Investor AB. Sometimes called the Nordic Berskhire, though there are so many "The XXX Berkshire" firms that it becomes tiresome! Founded 1916, I think of them like a publicly listed family office's portfolio.
Some introductory links mentioned in this post on the Non-US Stocks board.
mungofitch replies on Investor AB (US ADR IVSBF)

Jim