I'm a bit wary of artists being able to decide that so-and-so isn't allowed to see their work. I think "User Hide" should be sufficient for blocking. If you don't want to interact with someone, then blocking would hide them from you and prevent them from messaging you, but the only good reason for not allowing them to see otherwise public posts would be if they are abusing or harassing you, and that kind of behavior should just get the person banned from the site.