True, but it doesn't need to be a fairy to remove this annoyance. Take the King of Red Lions in WW as an example, he talked to you through the Pirate's Charm. Or Ezlo from Minish Cap. You could even go as far as to say Zelda from ALttP, with her talking to you psychically.But the nice thing about having a fairy is that they are small and don't get in the way. Think about the Wind Temple and the Earth Temple in WW. You had the characters following you around in those levels and you couldn't walk too fast or you would lose them and you had to constantly keep an eye on them so monsters wouldn't attack them. I don't think I would like to have to deal with a somewhat full sized companion the whole game.
I definitely think this girl is Link's partner, but I don't know what she is yet. Fairy. Ghost. Spirit of the Master Sword. I don't know.