Mention Dragon Claw in the Moves section of offensive DD, it's useful for Talonflame, Mega Vensaur, Mega Charizard Y, Amoonguss, and Mega Charizard X (to check it better), and should be used over Roost obviously.
In the overview, mention the big amount of Pokemon that Mega Altaria checks as a pro, and one of the main reasons to use it, as its defensive utility is fantastic, even when going max Atk and max Speed.
On the first two set's teammates, mention some lures or early / mid-game wallbreakers that wear down Mega Altaria's checks and counters, such as SD Diggersby, EQ + HP Fire Latios, SD +3 attacks LO Breloom, and Choice Band Azumarill with Superpower.
On the support set, remove Facade and Body Slam, Return outclassed both. Facade is very situational and Altaria likes to get rid of status asap anyway, due to the lack of lefties, while Return gets many OHKOes on Pokemon that Mega Altaria wants to check, such as Mega Gyarados, Mega Heracross, Garchomp, and Thundurus after SR (50% chance, sure OHKO after LO), making it way better than Body Slam overall. Body Slam can go to OO, but not any higher.
Mention that specially attacking Mega Altaria fits nice on sand balance / sand bulky offense, as it covers perfectly the weaknesses of Tyranitar / Hippowdon / Excadrill (Grass, Fighting, Water, Bug).
Good job AG!
QC APPROVED 1/3