So let's see I've:

>Beaten the Elite 4
>Completed the Looker Missions
>Caught Mewtwo
>Caught Zygarde
>Obtained all the skate tricks
>Got all the MegaStones (except Y exclusives)
>Got all the male trainer clothes
>Became a Grand Duke
>Completed the National Pokedex

Aside from conquering the Battle Mansion is there anything else to do in XY aside from the typical breeding and grinding teams for online battles?

I want to leave no stone unturned.