I like
Kaia and
Maia.
Gaia will be mispronounced incessantly, if you want it pronounced GY-ah.
Gaia is from Greek mythology (married to Chaos), if I am remembering correctly. Her name is pronounced Gay-ah. I know 2 women named
Gaia, and they pronounce it GAY-ah. If you don't mind the constant correcting, you should use it.