It's really true that the horse will rise to the level of your expectation (the ones that you actaully expect hard enough to enforce). So, it took a few months but this horse figured out you were not expecting obedience, so you dont' get it.
Expecting obedience means that you have utter confidence that it WILL happen, just as you envision it will. You envision that when you say go, he will go. And if you need to get firm, you do so with total confidence that your firmness will make him change his mind.
So, for when leading this mare out to pasture and she goes for grass, instead of trying to pull against her, you throw the lead line at her head. I mean , you give the lead line a big "snap", which sends the wave down the line and makes the line smack her in her jaw. First, you say "Ah ah!" and then give her the biggest toss of the leadline up into her jaw. If she jumps, so be it. If she does nothing, continue to snap the line ujp and into her jaw so that eating is a miserable experience. When she stops, you stop. The second she starts to lower her head, use the scolding voice and if she keeps going, toss that line at her again. When she'll stand for a few secs without going to eat, start walking forward, but you keep your third eye on her and the second she starts to go down, you scold/snap her. The important thing is to catch it early, when she is still thinking about it and knock that though out of her head.
Same with the feet. When you feel her just begin to move her foot, scold her warningly and pick up the foot higher. Doing the feet is more of a challenge, and you might need a more experienced person to help you because of the danger of being kicked. But for now, try my suggestion for the leading issue.