W00T!!! I finally hit Grand Duke rank at the Battle Chateau! I guess the next logical step would be to either use the Black Writ of Challenge I've just gained access to, or go back to the E4 and grind my life away. I think I'll hit up the E4 first, at least once, and then grind some more at the Chateau, hopefully encountering Diantha's Lv.85 team along the way!
My Chesnaught is Lv.72, my Clawitzer is Lv.60, my Delphox is Lv.99, my Venusaur is Lv.96, and my Tyrantrum is Lv.97. Not to mention my Lv.100 Heliolisk, Aegislash, and Azumarill!