18 year old toe-walker?

I've only seen one person that, like you, is a toe walker. He is bright, energetic, and ambitious. I agree with you that it is a trait, probably genetically linked. I think, energetically, toe walkers tend to be creative and may, as their body shows, have their head in the clouds. If it's something you want to change, you could try doing Tai Chi and QiGong, to encourage you to be more grounded.