I took an early retirement at the age of 59. I’ll try to answer your questions on order:
1-no
2-no
3-no- I put my money into bonds before the stock market crashed.
4-no-it’s better than I thought. I’m teaching guitar and bass and loving it. I wish I had time to waste!
5-much better – no more stress, i.e. corporate BS – I’m doing what I love to do now – although I had a great job in research I feel a lot more useful now.
6-If you take a lump sum don’t blow it on toys – If you are under a lot of stress get out now before it kills you: I made my wife retire way early because to stress – have a hobby or two that you enjoy to do – stay physically active

If you can afford it and you have the opportunity do it. You will not regret it!

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware