It's gotta be Hodor!
I reckon he's got a rain man thing going on there. I seriously think that dudes brain works on a different level to everyone elses. Soon as they find out he'll work out some formua for destroying the other's, and be crowned king as a reward. maybe
/me tries to invisage how knowing the number of toothpicks in a box will save the seven kingdoms
On a more serious note, I'd rather not have Littlefingers POV tbh, at least not until the very end. I like the way you never know what he's thinking, planning. Being in the dark about his motives and actions is what makes him so intriguing.