I don't see Cersei as a sensor. Ni causes most of her problems. I also think she naturally has Fi, but is forced to use Fe instead. She seems like an ambivert, so I'd guess xNTJ.
Littlefinger actually does seem to use Fe with ease. He could be an ENFJ. I guess he might be different in the books, but in the show he doesn't come across as particularly introverted or reserved about his feelings. In fact, he uses his alleged feelings for Catelyn to manipulate people.
Milisandre--xNFJ. She's pretty charming and good at persuading people, and although she's mysterious there's little proof in the show that she's introverted. She's usually around other people and doesn't seem bothered by unexpected company. However, Ni could still be her dominant function and she could be so committed to her faith that she's willing to put on any front to see her plan through. I can see TJ as well though. She is good at forward planning and likes to test a theory she has in the outside world, so I see a possible Ni/Te combination in her.
Varys--INTP or INFJ.
Sansa--ESFJ
Catelyn--I see more ESTJ than anything. She's action-oriented and uses Fi more than Fe.
Jon Snow--ISFP
Arya--ISxP
The Hound--ISTP
Tywin--ENTJ
Tyrion--ENxP
Jaime--ESxP
Joffrey--It's hard to say because he was unhealthy and didn't last long, but I do think he liked to be able to control his environment and liked clarity and consistency from the outside, so I think he's a Te user and possibly a J. Obviously he did not use Fe much. He preferred to be blunt rather than tactful, and though highly sensitive he preferred to appear otherwise. He was young and immature, so it's difficult to see how much foresight he might have. He didn't really have to call most of the political shots. Were he less spoiled, and forced to make important decisions, it'd be interesting to see what would do.
Daenerys confuses me. I can't tell if she uses Fi or Fe. She's good at assimilating into different groups and had good diplomacy for her level of experience, yet she also has some strong, unconventional (for the time/place) views that she refuses to give up even if it hurts her popularity. It was only when individual people came to express their tragedies to her (in the show, at least) that she yielded a bit. That seemed very Fi to me. I think whatever feeling function she uses guides her the most.
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