Id be careful of Haxorus, DD Haxorus really rips your team a new three (not a new one!), especially with Brick Break. Nothing can stop it at all. Also, you have a HUGE MASSIVE weakness to those SD/Sub/Acrobat/EQ Flight Gem Gliscors which are becoming popular. Id look into something faster to help deal with those, which seems to be this teams main problem. Its rather slow.
Also Gastrodon pretty much needs Earth Power to significantly damage certain targets it can check such as foe water types, especially Tentacruel who will set up T-Spikes on your ass all day otherwise. Recover/Ice Beam or Scald/Earth Power/Toxic is the best set imo. Earth Power also hits the annoyance which is Jirachi.
Also i prefer Lum Berry and Moxie on Scrafty with Hi Jump Kick over Drain Punch, ive always swept more like this easier. Drain Punch always seems really weak lol. Up to you though.