Great work FP. And very interesting.Since there are no returning stars, Jon's position is a very positive indication of success. I think Keith (spit) is just an interesting character, and no matter how many confessionals he has, he has only an outside chance of being in F2 or F3. I would predict that he goes at F4, unless somehow he wins immunity at that IC.
The strong alliance is at the point to where someone who considers him or herself to be #5 in the alliance (maybe Nat?) could really begin to consider getting rid of one of their own. Of course, if someone did that they would blow up the alliance, and if the others caught on before the vote, he/she would be in danger, and Jeff will be asking his usual probing questions. Risky, but Nat does have a HI, so she might give it a shot.
I'm beginning to consider a Nat boot. Especially if she fumbles and her attempt to double deal is revealed. Risky, but maybe worth a try, because she has to be aware that the worst case would be a 4-4 vote, probably between her and Jon which she could win, and best case would be a Jon boot if her present alliance could somehow be persuaded to split their vote.