It’s definitely a risky move, for the reasons you already called out. But sane? Yeah, probably. I’ve known a few people over the years that have done similar moves: dropping out of high-pay/prestige positions due to the stresses and general unhappiness. They’ve almost always ended up generally happier for the change. Just don’t be afraid to acknowledge if the move isn’t working. Don’t talk yourself into staying in a bad situation because you don’t want to admit that the move isn’t working.

(but also: drop an update in a few weeks. I’m now curious to see how this goes for you.)