" If you are walking and he wants your attention or he is trying to dominate you, he will just grab your leg or your sock and pull."
Harley is just trying to get you to play. What do you want him to do when you are walking?
I want my puppies to be attentive and want to walk along my left side. I would encourage my pup to be focusing up at me and rewarding right along my left seam of my pants as I walk along. If he is focusing/walking along eating rewards for good behavior he can't be pulling on my clothes.
You want to encourage alternative behaviors and reward for them. So every time your pup is doing things you don't like think about it and figure out what you want them to do instead of that and reward for the good behaviors. By lots of rewards for the good behavior you will set in good habits and the behaviors you don't like will slowly stop. But it takes lots of consistency on your part.
"He also has a problem with jumping up on the couch with his front paws and no matter how many times I tell him to get down or set him down, he is right back up. SO STUBBORN."
He really isn't stubborn. He again wants to be with you and involved. He doesn't really understand what you do want him to do. It is easier to teach what you do want vs what you don't want. Again, figure out what you want him to do in place of putting his paws on the couch and ask for that behavior and reward for it.
Believe it or not but scientifically it takes about 500 repetitions of a good behavior with rewards before they really really know it.
Patience, consistency and having a plan of what you do want Harley to do depending on the occasion will help him become the dog of your dreams.