Yeah, as others have pointed out you're pretty weak to fighting mons, Terrakion and Conkeldurr in particular. While this is an offensive minded team I think that a standard defensive SD Gliscor over Salamence might help you to deal with the above threats and some others as well (Breloom among the others) while not twisting too much the concept of your team. An impish Gliscor with taunt or protect\EQ\swords dance\ice fang or facade and an EV spread of 252 HP / 184 Def / 72 Spe is what I'm suggesting. I'm listing protect as an option just for those annoying volt turn teams that are invading the ladder (fuck you Ojama). Gliscor would also give you a backup plan against Scizor, should you lose Heatran prematurely.
Another option, as the above pointed out, would be making Salamence bulky, giving it roost and a more defensive EV spread but I'm not sure how effective it would be against Terrakion and probably even Conk.
I really like this team as it shows that hail offense is an underrated, yet effective playstyle in OU. Good luck with the team.
<ginganinja> can I add Pocket
<ginganinja> to his own blacklist
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