Emily.. Hunter is never going to be a hunter. He is a wimp and you don't push him. Hunting dogs are working dogs and they will work no matter what. If he is being a wimp becaue of the cold weather, then he isn't going to work for you when the weather changes.
All you say is "I cant"... You can't train him any further because you need a field or water and a gun. I know of many people who train their dogs to retrieve and pattern.
If he is so destructive and the exercise isn't taking the edge off, then you need to push him and MAKE HIM TIRED.
But I forgot, the dogs call the shots in your household.
I agree with alty, you claim your dog is so awesome with retrieving and dropping items, yet he runs away from you in the house, won't drop when told and constantly grabs inappropriate items. That doesn't sound like a very well trained dog to me.