Those who say you can't get a horse to put ears up if sulled up are wrong. By increasing intensity of your own body language and using your voice or lightly shaking halter and telling horse to shape up, you can get those ears up and horse in different frame of mind quickly. In herd situations the lead horse does just this. Leader rightly regards those ears pinned as other horse having attitude, and fixes it.
As to OP.
Looked at the few pictures you have...and the one where is following human? That is an attitude and not a good one either. She thinks she is running the show in that shot, and not a good thing for one to think. You'd be better off to not let her follow you like this. She gets a little bigger and she will come up, wheel and kick out and then you will wish you hadn't done this. And one where she is in front of human is not a good idea either to do with foal, as gets them too familiar and too cocky.
You don't need to let this horse or any horse lick you, ever. Bad habit to get into, and darn sure hard to break later. And if horse is showing ear pinning now, coupling that with licking will make problems down the road.
As for popping horse in mouth making one headshy? BS. Hit the end that offends, and make it count too. Never seen a horse become headshy IF the person was determined to get point across. If someone is flailing away without intent to end behavior, it will make a horse worse in terms of it will come back at you harder.
But never had one become headshy because of getting popped in nose, or smacked on jaw. Have got the unwanted behavior stopped though.
As for whoever said horses don't do things to hurt or displease?
That is also BS. Either you don't have that much horse experience or you don't pay attention to what is going on in terms of dynamics. Horses have a mind of their own, and many times what they want or don't want is expressed with a kick, or they sull up, but when they kick? What do you think they are doing? Pilates?