So is Soraka a Vastaya?

Nope. Soraka's got other stuff going on. Cosmic stuff.

She is a twinkle twinkle little star, that doesnt know what she are.

I think she's still a former goddess.

Soraka would be most comparable to Aurelion Sol or Bard. She is a cosmic entity who gave up her immortality to help mankind.

http://leagueoflegends.wikia.com/wiki/Vastaya The list of vastaya are Ahri,Nami,Nidalee,Rakan,Rengar,Swain,Udyr and Xayah Edit: and wukong

Soraka was a godess but decended to the mortal world because she tried saving.. warwick? i think? that used to her lore atleast all i know for sure is that she used to be a celestial beeing but felt too distant to actualy help the people of runetera so she decended and took her cool starpowers with her.