For skinning? Who uses a knife for skinning a deer?
Except for cutting a ring around the legs and two splits across the starting side, I just pull the skin down and literally rip it off..
I've even seen some tie a rope to a 4 wheeler to pull it off in under 5 seconds.
As for gutting, any 4 inch sharp smooth knife will work.
For processing, I like to use something at least 4 to 5 inches long..
Never use a serrated blade.. smooth blade only and frequent use of sharpening stone.