Well not to burst your bubble but you could ALSO ignore to listen to Navi. Fi popped up more than Navi did. My least fav companion? That is a tough one. Unlioke many others I actually liked Ciela. She was fiesty and had a personality. She shower her emotions. I loved her. I think I have to go with Fi. She was robottic to me and didn't show much emotions. Yes she was helpful and gave you information but still she was kinda coldWell you have some points about Fi, but she's nowhere near as annoying as Navi. She doesnt yell "Hey! Listen!" when she wants to give you advice, all she does is make the sword flash. You can choose whether or not to hear her. Big plus.
Spirit Zelda. It just made the plot so awkward to have her by your side the whole time. Sheik was a different concept cuz she just guided u occasionally.