Jon going back up north is the least bothersome thing about that ending. Of course we still have a nights watch, we need somewhere to send the bastards.
But now that there's peace with the freefolk and no white walkers to worry about, castle black can just be a party fort. Shame Ser brianne didnt accompany him on the trip there, i really wanted her and tormund to fuck.
I don't know what's up with arya though, suddenly she's christopher Columbus or some shit.