Honey, you are beautiful, no matter what they say. And if you rock that confidence in that statement, then nobody can touch you, and you will be a goddess to them. Confidence is a very attractive trait, and the more confident you are, the more attractive you are to others.
As for the spell(s), I recommend your simple wishing spell. Or maybe even something more elaborate, if you are desperate. But all in all, I seriously doubt that you need a spell to make you beautiful.