Stylizing Skill
I'm sure that this has already been suggested, but I think it would be really neat if there was a skill for stylizing horses. Many riders in real life competitions choose to style their horse's mane and tail, and some even clip patterns into their horse's coat. It would also be cool if we could by tack for our horse's, although I am sure that is already planned. We could have beauty based competitions where the community votes on their favorite horses based on their conformation and looks.