OP, don't know you but rooting for you

Re eating/getting healthier,

1) food: this guy Rip is truly a lifechanger (esp if since you're in the zone when it would be smart to look after your heart: https://mealplanner.plantstrong.com/

2) Lose weight (this approach might be appealing to your engineer'y instinct): https://www.fourmilab.ch/hackdiet/

3) Exercise:

- Warm up (DO THESE): https://www.youtube.com/watch?v=-QWyyHfARNI

- Try to get through a round of this w/ good form + then try to do 2, 3, etc: https://www.youtube.com/watch?v=XTSIqbuZC0Y&t=369s

I don't have any career advice for you, leaving is one option but consider that it would great for you to "skill-up" the people around you so when you leave it isn't like they lost their Golden-Boii, but rather bow out like a Bob Iger at Disney & leave them with a glorious future blah blah