Bran and his tree buddy are gonna sit in their masturbation chamber while they spy on naked women undressing next to those red-leafed trees. The little kid-like creatures will provide them food and clean up the cum. This will continue until G. Martin dies or until the series ends. (Yeah, Bran will probably be able to control a dragon).
Tyrion is smart but physically weak, so he'll need to attach himself to someone powerful (like he always does). Tyrion has a knack for survival, so I expect and hope that he'll make it. Also, I'm expecting him to team up with the Dragon Girl, who has serious faults of her own--e.g. unable to effectively use her dragons, unable to make reasonable political moves. E.g. let the dragons loose and pay people compensation for their dead children. She shouldn't have left so many enemies around her, so she'll be duking it out for awhile in the Free Cities/Whatever Cities region, unless she makes the hard choice of abandoning her city and taking her whoever with her (good luck, it's not cheap to move a big army by sea. She'll probably lose a lot and then regain it in Westeros or closer by).
What's up with that purple(?)-haired kid on some boat, claiming to be some bigshot? Is he a supposed Targayrian? (No, I don't exert enough effort to correctly spell the proper names).
Oh, and there's got to be SOMEBODY capable of training dragons. Those things are practically worthless, and whoever can command them can take them from that soft-hearted dragon lady and do some real damage. I'm thinking (and hoping) the dragon lady, Danaerys, gets killed. I'm really tired of her story.
I don't see Sansa killing Littlefinger. She's been a coward her whole life, and for her to redeem herself with that act goes against the grain of the GoT series. There's many people like her that willingly resign themselves to their own slavery, so she should serve to remind the readers and viewers of that fact. Even better, she gets sold to one of John Snow's enemies who'll try to use her as a bargaining chip, but that probably won't happen since Littlefinger needs her to indirectly control the Vale.
Stannis, John, the 'Wild People', and whover's charging to the wall are gonna fight some big battle against the undead, cold dudes. Winter's coming, so the undead cold dudes can push further south. Expect fun. If the Lannisters keep losing more control over the realm, then the Ramsey/Bolton crew is going to ditch them and place their bets on Stannis and/or John (one of them will probably die in battle or murder the other).
Arya, the soon-to-be professional assassin, is the biggest wildcard. She could kill anybody and shift the whole series, so it's hard to say what she'll do. She may even kill Tyrion.
Also, if you got spoilers
beyond the book series, then use the spoiler tags please.