I like how you think outside the box. It's funny because I relate to so much of Fiona Apple lyrically. At one point watching her in an interview also, I could have swore she was delta NF, despite all the supposed Fe demonstration (so I actually was like...could she actually be IEE???). I also agree that not all rational types and EII are super stable/completely introverted etc. as people like to imply. I considered EIE for Fiona too due to potential Si PoLr with all her health issues. There are so many shades to all of the typings and a plethora of historical information backing why someone's type may seem different than it's more classical description. Very cool. From what I know she seems IEI to me, but I don't know a lot.