Right now, I would like to work on his halt. What we seem to have going on is a halt on his terms, on a angle, after a few steps. As much as I'd like this to be a nice halt and not me jerking on the reins or anything like that get him to halt the first time, I'm lost of how to fix this.
Any ideas? Thanks.

An (bad) example of how he looks at a halt.
If we were riding along the side rail and I try a halt, this is how he stops in general.