I'm not saying I don't want Arya to kill Cersei but how is she supposed to get into Kings Landing, into the Red Keep, close enough to Cersei and then kill her all without being noticed and captured.
I know she can do the thing with the faces but unless she gets Jaime's face and kills her when they're about to shag I can't see how going to Kings Landing wouldn't be a death trap for her.
I reckon she'll go to Winterfell, have a Stark reunion with Sansa, wait for Jon to come back, even bigger reunion, wait for Bran, fucking huge reunion. Then live out the rest of there lives happily ever after at Winterfell and let Tormund and Brienne deal with the White Walkers.