I wouldn't call it ugly. :( I know it is YOUR opinion but, it that just basically calling everyone who had piercings,tattoos, and dyed hair - ugly.
My friend Nicole has about 5 or 6 piercings in each ears, and one in each stretched, her nose pierced and everything. She dyes her hair a different color (Blonde with pink, red, orange, green and so on) almost every week -- She is the prettiest girl I know.
Not letting your child do what they want with THEIR hair or their body, is not letting a child live or be a child.
It's not going to hurt them to pierce or dye hair (unless they do it the wrong way, which is something that should be talked about) rather than having sex or doing drugs, which could hurt them.