Most people who are inexperienced at cleaning game think that bigger is better when it comes to knives. Nothing could be further from the truth. The best skinning knives have blades that are no more than about 3 1/2". Some of the best skinning blades are only about 2" long. When skinning, you want the blade to be an extension of your finger.
My favorite skinners all have blades less than 3" long with rounded thin points. Skin the hog soon after it is killed and most of the skin can be pulled off. Skinning is much harder after the hog gets cold.