[Southpaw]

That is a fine looking dog. Has a good shape and sounds like he has a solid disposition.

Trained and been around a good many really top quality dogs either for general hunting and some field trial. Its hard to tell someone how to train their dog since different motives and experience/expectations of handlers/owners, different breeds, and personalities of different dogs, but there are several good techniques to training heel without a lot gizmos if done correctly. As young as that dog looks you have done well to teach him those things thus far with any consistency. I commend you and your teaming for him to learn what he has.

BTW I have never seen a setter heel worth a flip, but most of the ones I knew were mostly exclusive bird dogs that stayed in kennels for most part unless they were out working/hunting. You are correct about him being distracted when he is out walking with you, his nose probably is dragging him one way and you want him to do something else. Be consistent and over time he will probably acquiesce and pick up on it, or he won't. I have seen plenty of bird dogs forced trained to retrieve, but getting them to do it in the field is different and have seen plenty of dogs compartmentalize training.

BTw when training to heel don't just walk in straight lines, just pick one side for him to always heel on, typically off shoulder or opposite of gun side. Work zig zags, box patterns into him and away from him, circles. Keep him in proper cadence and position to your side when he when out of sync tug on leash and say heel and reinforce at what position of heel at your hip you want him at. Work starts and stops and keep in sync. He is suppose to be paying attention to watching you walk. If he pulls ahead, walk towards him and pull him back, and also walk in 90 degree other direction. He will learn when at a heel if is ahead and cannot see you then he is not at heel and in sync with you. Also don't let him lag or trail a little behind, that is not heel either. Keep lessons short but intense, and do no more than a few times a day at first but so it at least once a day and praise him well when he does it.

I would also teach him "high on" or "hunt on", that lets him know when it okay to run amuck and let him be a hunting dog and explore with his nose. You will find this is the easiest command to teach.