Like most farmers if we knew what it took to raise the production levels it would have been done years ago. There is a reason that when you drop into the good land that is born that way ,the building are better and the area just looks more productive. It is the  affect of years of slightly better than normal crops. not much you can do about some of it. You can help the areas that have been neglected and bring them up a few bu but you can't turn bad to good. Maybe bad to  better
 Around here NW Pa the land changes from one side of the road to another,almost makes you think they put the roads in for that reason it is so pronounced. Land on one side is nice and dry in the srping and stays moist all through the growing season. The other side is clay ground or hill ground.   Do everything just right and if the weather gods are on your side you will get a decent crop.Trying to get one equal to the other takes time and money. And it still won't be as good on the bad years
 biggest problem I see is the clay guys want to plant when the dry grounders are planting but the best crops on clay will be planted weeks later. It's all in knowing what your ground will do. And yes sometimes it's better to settle for lower bu. with less cost.Profit should be about the same.That is until we get a bad year when the ground shines again.
 My advice is make sure your getting the top yield on the good ground and do the best you can with the the other.