You could go with Energy ball so that way you can put full EVs into S.Attack but it is good either way.
Scald over Surf the burning chance is way to good to miss. If you really want more power to your move you should go with Hydro-pump(I know it has low acc but it is worth it) though I prefer Scald.
Why no EVs in S.Attack?? Put 252 S.Attack and the remaining 6 in HP. Though you seem to have very Few physical Pokemon, you could go Physical with him: Outrage/Dragon-claw, Stone-edge, Hone-claws, Shadow claw with Jolly nature, and 252 in Attack instead of S.Attack.
No wonder this thing failed against trachy, why have Solar beam on him when you knew he was going to use Hail too? Magma-storm is something to consider(instead of Flamethrower), Flash cannon over Iron head I mean seriously you have an Attack reducing nature and no Attack Evs and you go with Iron head? Hidden power Grass or Ice over Solar beam(At least until you are facing a Sun team in the loser redemption battles).
Another special attacker? This guy is amazing as a Curse tank. Go Curse, Waterfall, Earthquake, Avalanche. 252 Attack, 252 Hp, 6 S.Defense.
Good, if you want priority you can swap S-dance for Ice-shard.