The thing is, there are some horses that 'frame' doesn't help slow them down. I can ride my horse, post 'heavy' in the tack, but the instant he sees a fence, he's gone, regardless of what I say, regardless of bits. We canc ome back after a fence, we don't go galloping off, he just will not approach them 'nicely', and because of it I'm fighting him, and he ends up jumping more inverted.

Poles before and after fences are what I've found have really helped, likewise, keeping him 'wondering'. With fences (four or five) around an arena (on angles, quarterlines, centers- no combinations, just all little verticals around the arena), switch around the turn, turn left, turn right, go to a different fence from a different direction, just keep him guessing. It really helps him come back to me and NOT be a jerk about it.

Other than that
Gymnastics. I love bounces and one-strides to bounces, ect.

And, the trouble with asking a horse to halt immediately after a fence, sometimes they'll figure they're supposed to stop EVERY time, and, if your horse fights for his face before a fence, he's going to land and you don't want to fight for his face right after. It's better to 'negotiate'. A halt is no negotiation, at least in my experience. I'd rather canter two or three strides in a nice, balanced fashion and then trot and walk and halt when what I'd like to do is halt, and what he'd like to do is gallop with his legs all over the place.

“There's a lot about discovering who you are and how difficult that is, and it never stops.”
- Libba Bray