For skills then, how about:
Balance, Climb, Concentration, Hide, Jump, Intimidate, Knowledge (nature), Knowledge (nobility and royalty), Knowledge (religion), Listen, Move Silently, Search, Sense Motive, Spellcraft, Spot, Survival, Tumble
Religion is due to her background like nobility would be.
For feats (13 right?), I would go with:
Awesome Blow, Dire Charge, Flyby Attack, Hover, Improved Bull Rush, Improved Critical (bite), Legendary Tracker, Power Attack, Run, Snatch, Stealthy, Track, Weapon Focus (bite)
And to get this out of the way, do you think we need more on this? Does it look sound enough as-is?
“Astral Form” (Su?): Gaumahavi can use astral projection on herself only, as a standard action. She leaves behind a small portion of herself, consisting of a form of purple dust, on the Material plane. This form functions as the gaseous form spell, and allows her to see and hear anything that goes on around her. She can guide this form to any location on the Material plane, using her winds. She can reenter the Material plane wherever her dust form exists.
She can polymorph into any predatory animal or assume astral -form at will. When in astral form, a shadow of her body, in the form of purple dust, remains on the Prime Material Plane. This form can only be struck by +3 or better magical weapons. By dissolving one dust body and forming another in a different part of the world, she is able to move over great distances instantaneously.
Ecology: In astral form, Gaumahavi draws her sustenance from the mystic energies of Toril. However, in normal corporeal form, she is a voracious carnivore.