I just find some of the rules a bit crazy. No glitter, but we can alter the color of the horses mane/tail. We cannot use a fake tail but can shave all the hair off the face and use black make-up to alter the color of the face. But it is against the rules to use white chalk on the white markings, because that will change the look.
And i see nothing wrong with a sun-bleached black horse, I love the rich, chocolate bar look it gives to their coat. I see nothing wrong with hair on the muzzle, I think it looks really silly when the muzzle is shaved bare, same with the eyes.
Just my opinion, which really doen't mean anything at all.
P.S. I really like glittered hooves! doesn't look any more out of place then black polished hooves on a white legged horse. JMTCW.