You are right in training them in the two steps. ONe to stand and not move forward to the handler when modeling, to let you back off a bit so you are not obstructing the judges view. When you are a few steps back from the front of the horse it give a prettier picture!
When trying to get ears, really try different things to see what the horse reacts to. You can try unwrapping a peppermint in front of them while they are in there stall even, let them get used to the sound, after showing you a nice alert look with ears and stretching the neck, put a peppermint in their feed bucket. If they like them it wont be long until the wrappers get ears pretty well and you can use them in the show ring. Sometimes if a horse is used to a pelleted feed use a small amount of sweetfeed in you hand and see if that helps. Many will perk up for that as well, you can let a few grains dribble out of your hand to interest them as well. I always have three or four things for bait in my pocket for every class! If they start getting bored of one thing, switch to another. Also pace yourself as to when to start your horse modeling. If the horses are still coming in and the judges backs are to you in a halter class, then you can set them up but not ask for the ears and neck just yet, save them a bit. But be aware of where the judges are at all times!!!!
I also dislike it when other people use the louder training methods, it distracts many horses and can ruin a class for other people. Like the shaking of the little tic tac containers, etc.
If you can get your horse to model and show for something inedible, the look is prettier and more alert. Some horses will reach forward with their ears only partway forward, and I call this food ears! NOt all horses though, some just will model beautifully for about anything! With a nonedible bait, you wont get the lipping or bored reaching out as much.
It really depends on your horse, but for one that doesnt go for the nonedible things, I have tried nickermakers, and practiced at home, making a scratching noise on the nickermaker with my fingernail, when the horse looks really pretty in the stall with ears perked up and stretching up and out nicely I then put it in the feed bucket. If they like them it doesnt take long for them to associate that noise with the treat they will get.
If your in a huge class and the judges are at the other end, its ok to give them a treat and let them relax a moment but still holding their pose. That way when the judges come back, or walk the line at a distance comparing horses, you can be ready to get your horses attention quickly and be modeling beautifully right away.