I also work outside all day and nights too . All be it I'm just a lazy heavy equipment operator but I do have to get out and work underground quite often .
The big difference between work and play is that mostly while working your moving and keeping circulation and blood flowing which will help keep warm (er) .
Things i do include sitting in a tree stand or standing on the ice all day, I get cold. Mostly my hands and feet. Standing on the banks of a 33 deg river while only casting repeatedly will make me feel cold much faster then casting for 15 mins then walking a bit to keep circulation going again.
I have had bootfoot neo waders , while they are not the most elegant or comfortable waders , they do provide the best warmth, esp when you put some chemical heat packs in the feet. I think it's because there is more air space to allow better circulation . That's just me and my experience .
I don't however own them any longer and instead have stocking foot breathables , I get cold and need to take warm up breaks often, its the only solution I have found.
A nice warm hat, some good wool gloves and a wind proof outter shell jacket are some of the things that have made my torso up at least feel comfortable .
Good luck with the tie and stay warm out there