I have always gone with an outfitter. The reason is it is a long way and unless you know where you are going, X or someone, a local is helping you, I did not want to go on a 18 hour drive for a Waterfowl Easter Egg hunt.
North Dakota we always went around Halloween, spent many there at that time as it freezes up early. When it does the sky's can go from a wonderland to barren overnight and you are done.
Nebraska is more of a timing thing as the Platte River and secondary streams are/can be spring fed. You can always hunt greater and lessers, outstanding hunting.
In closing here is a picture of a pit that had several Jeff Foiles goose videos filmed from it. It is a family owned property and our guide/son of owner landed the geese on the lid, before calling the shot. He said before hand let me show you how we do it here.