The irrationality of disgust suggests it is unreliable as a source of moral insight. There may be good arguments against gay marriage, partial-birth abortions and human cloning, but the fact that some people find such acts to be disgusting should carry no weight.
We are constituted so that simple acts of kindness, such as giving to charity or expressing gratitude, have a positive effect on our long-term moods. The key to the happy life, it seems, is the good life: a life with sustained relationships, challenging work, and connections to community.
Relying on the face might be human nature - even babies prefer to look at attractive people. But, of course, judging someone based on the geometry of his features is, from a moral and legal standpoint, no better than judging him based on the color of his skin.