The only thing I would have done a little different is I likely would have used a single-tree between him and the tire. You didn't seem to have a problem with it, but I've seen horses that had a freak-out whenever the traces would come tight and come together, putting pressure on the outsides of both hocks. Using a singletree keeps the traces at an even width regardless of how much weight is there.
We kind of want them to freak out. They need to learn while we have more control that the traces can get tangled up around their legs, and step on the tires, etc., but when we say whoa, and they stop, and we untangle them, but no harm is done, and that is how they learn to handle potential hazards when put to the carriage.