The part about "never occurred to me to ask what I'd be giving up" is what I'd push back on a little. You can find that out pretty easy by talking to the guys who already took the job, ask them what their week actually looks like now, how many nights they're still at the shop, whether they still get to touch the work or just push paper. The $8k sounds nice but run the math on it, because if you're suddenly on salary and working ten extra hours a week, you just gave yourself a pay cut per hour. Some of those guys being miserable might just mean the role isn't set up right, not that the job itself is bad.

Man, I feel you on the mag grabbing. I pour a lot of flatwork here in Oklahoma and had the same thing happen on a hot day, that mag float just stuck and tore up the cream near my expansion joints. I keep a broke-in wood float for the wet stuff and only pull out the mag once the mud stiffens up enough that it won't grab. My rule now is wood first pass while it's still shiny, mag after it sets a bit. Sounds like you already got it figured out better than most guys.