When Tyrion asks Bran if he'll wear the crown and lead the Seven Kingdoms to the best of his abilities, Bran cryptically answers, "Why do you think I came all this way?" So, you're telling me that Bran always knew that he would be king? How long has he known he'd be king? Has he withheld pertinent information along the way that might've helped save lives, or change the course of things, all so that he would eventually end up as the new King of Westeros?
In all likelihood, the answer is "no" since Bran doesn't exactly seem like the murderous, power-hungry type. But who really knows?! Now that he's the Three Eyed Raven, his normal human personality has been wiped clean, leaving a sentient crystal ball wrapped in a big fur coat in its place. All I have to say about his character is: ugh.