Help with horse taking off uphill?

[Skhosu]

Hi guys, so we have a hill, its like a triangle with the bottom part of the field along the bottom of the hill and bottom of the triangle, then a steep uphill, then back to the bottom on a gentler slope.
So we gallop up it on the horses fairly regularly, so they all think gallop. I've been working with my neurotic 3/4 tb to try and get him to canter. He is in a snaffle and when he gets tense draws behind the bit rather than pulling, any time I try to trot up the hill he attempts to canter. I have been swinging him round immediately as soon as he tries to canter (he walks down the hill on a loose rein). And I am sur ei is just a matter of retraining him to walk, trot or canter up the hill as requested. We can now walk up the hill with me in the jumping seat. Even trotting along the bottom of the field he hangs to the left side, i.e trying to turn up the hill, I did leg yield today to try and stop this which helped, in trot, but trying to canter along the bottom he just goes super tense and on the spot.
I am also worried about his confidence in going into the bridle as he is a v. sensitive horse and doesn't seem confident to trot on, and if I ask him to, canters off, so I have to pull him back and vicious circle. Any suggestions welcome

 

[Booboos]

Mmmmm, not sure if this will help, but it sounds like he's not very balanced yet which should improve with more schooling. In the meanwhile out hacking I would concentrate on simply getting a reaction to the leg (which can often be a problem with horses that are behind the bit), so if he canters I'd let him get on with it (provided he does not tank off with you, but he does not sound like that kind of horse). Given that he also 'gets stuck' and canters on the spot, I'd work on teaching him that the leg means 'go forward' and not worry too much about the pace as long as it is forwards. I wouldn't pull him back at all if he offers to go forward in any pace, either trot or canter. Hope this helps!