My first design was based on the UN Flag with the wreath for peace, but the stars represent the continents and the male and female symbols represent humanity.
The reason there is more blue than green is because there is more water than land. I was also unsatisfied with this a put the green end at the hoist and the symbol so that it includes both green and blue.
As the moon is supposedly claimed by man I also designed a moon flag. This is a black flag with a white disk over a blue disc symbolising the moon of Earth. In the canton there is an Earth Symbol symbolising its sovereignty to the Earth.