I know it's been said before, but you also need to look at hunting pressure. It's amazing how many ducks will be around after a week of not being able to shoot at them. That being said, I would love to hunt at least the first week of January in the middle zone. People can post the count numbers of "peak migrations" but it's all a statistics game. I want to shoot fully plumed mallards in January over a field. Or we'll take an ice eater and bust open a hole. I find it very difficult to shoot mallards in a field when there is open water everywhere, especially if you are surrounded by clubs. Then again, I'm not that good at duck hunting, so who knows. I have a few videos of ducks piling into fields by the thousands while we were goose hunting this year after the middle zone closed. I think part of that is because all the farm ponds, duck lakes, and irrigation lakes were all locked up. I also think that they were pounding the fields that we were in because we hadn't touched that field during duck season. I'd be willing to bet if we duck hunted that field a few days in a row, they wouldn't be back for awhile. All in all, I think the seasons are "ok" where they are set. I would rather push the north zone back a week but if it doesn't happen, it's not gonna make me quit hunting. I'd like to see a week or two split just so the birds get "fresh" again for a few days. I can only imagine that the first few days after a split would be pretty awesome.
Work hard, relax hard.