I've played the game for a while but just hired companions for the first time. Two suggestions, neither really critical, but just a couple of points where the game seemed less realistic than it does in general:
(1) Make companions reject boards as payment, since they make them. I recently hired a couple of companions to help build my cabin. Once it was clear I had enough logs for my cabin, on a whim I told them to split some into boards. They were both fairly skilled in timbercraft, so soon there were piles of fine and even perfect boards around camp. When they started to say they wanted to leave and wanted payment, I paid them with the boards they'd made. Using fine boards, they hit their carry-weight limit just short of the amount of "gear" they wanted, but the remaining balance was a couple of arrows per companion. If I had used perfect boards it seems like it would have been possible to pay them entirely from the products of their own labor. Maaaaybe that's fine; it's sort of like a little Marxist lesson on exploitation of labor built into the game (would've been even more so if I'd lent them axes, but these two had their own already). But the realism seems a bit strained that this would be acceptable "payment" when they could just have been splitting boards on their own time, plus the time they spent making those boards was about 5-10% of the time they'd been with me.
(2) Have companions sleep. It seems like companions just . . . don't sleep? I'd work all day along with them, and then as I was "exhausted" and about to go to sleep, I'd give them orders to go chop trees or whatever, and it seemed like they'd keep working through the night. I wasn't monitoring their work output carefully -- perhaps they stopped right as I went to sleep and started up again right when I woke -- but sure looked like they were not sleeping. Never saw any Z's by them for sure.
Another companion nice-to-have would be adding "chop wood into blocks" as a companion command; the block is a nice unit of wood for smoking/staying warm in winter.