Okay, what's with your EV spreads? You seem to have the stat abbreviations confused, man.
What's the point of Ferrothorn using Special Attack EVs when it's not using Special moves? (its Special Attack is downright terrible) It should use 252 HP/88 Def/168 SDef (Special Defense).
Get with the Black 2/White 2 changes here; Volcarona needs a bit more Speed, as seen with 160 HP/252 SAtk/112 Spe. What's the point of running a Modest nature if you're not investing in Special Attack at all?
What's the point of using 4 Attack EVs if Hydreigon isn't using Superpower? These should go into HP. Since none of your other Pokémon are holding Leftovers, maybe you should give that item to Hydreigon.
Again, get with the Black 2/White 2 changes; Gliscor should use 244 HP/28 Def/236 Spe so that it can always outrun Lucario.
Starmie is meant to be an offensive Pokémon; why are you investing so heavily in Special Defense? It's somewhat frail, so the main EV spread should be 4 HP/252 SAtk/252 Spe. I think Starmie deserves an Expert Belt, since it has good coverage.
Other than those EV spread nitpicks, team looks good.