If you want to put more buttons on your horse, I would add a neck string. I've seen a lot of bridle-less riding done without one (I've tried it as well), and although you can control a horse to go in circles, changes of lead, gait, etc.--there is no finesse. There is no bend. I use the neck string to have separate control of the front end--if you want things to get more technical, then you're going to need more 'buttons'.
As for his hind end, he looks very lackadaisical at the trot and canter/lope. I would start posting, push him into a nice working trot to get those legs to move under him--and THEN start to collect it into a jog. Same for the canter. He's also falling onto his forehand during downhill transitions, but I'm sure my paint would too 90% of the time bridleless because it's easier. ;)
Proves there's nothing 'magical' about bridleless--just takes good training! Now it's time to work on finesse. ;)