If you knew you were chosen among all individuals in the world to receive from God a miracle in which you'd be turned into the most beautiful woman or most handsome man ever, and you'd need only to ask for it, would you? Initially, it could please your ego, make you feel "good", but soon you'd find yourself so lost due to so many people wanting to be close to you because of your appearance, that you'd start feeling hopeless of finding someone with potential to really love you, thinking that maybe it could be also preventing someone who would like you for who you are from even trying to talk to you to know the character you keep beneath that skin. It would be a fate where you have the whole world falling at your feet, while the one who would matter to you only observes at a distance that wall of people between you.
A sensible soul understands that Love is the greatest gift, so he or she would ask for It instead to please another sensible soul who likes them. Because both can perceive that the presence of a good looking person cannot be compared to that of one who has Good and is good. Do you realize how unbearable it can be to live with another empty soul who doesn't even seem to notice you're there, who has nothing to share except complaints? And no matter how much you "change" to please their ego, it'll never be enough, it's a scam, they're never going to really love you. Would you like to change your appearance to offer the world? You'll need more beauty than God has to give.
When you're in front of a mirror, are you telling your true or false self that what you see could be better? When it's your false self you're talking to, it takes control and makes you vain, and all you can think about is to "change" and please the world; when it's your true self you're contemplating, you have a sense of purpose. There's nothing wrong with wanting to look good, however we are surrounded by a world full of people who are not looking for Good, their "desire" is shallow. So if you're not a robot, only a biological machine, actually a divinely made subject, one millimeter below that surface, you're in trouble there, because no action you perform will be able to make the distracted mind see you as another kind of precious object.
I'd say to God, "No, first give me Love, secondly someone who would change for me, seek Her; and then you can change me into the most handsome one if you want to, not as gift to me, but to her".