the team's pretty solid, i liked it! but, offensively speaking, don't you sort of have low physical power? your entire team is specially based, I can see it having problems in taking down stuff like Snorlax and other special walls. and defensively, as you said, it lacks dark resistances.
well, the only change i can think of is using a SR Cobalion of a Jolly Nature, with 244 HP / 72 Def / 192 Speed evs, over Azelf, so you can deal with Snorlax (and you can beat CurseLax if you use Taunt on it), Weavile (I think you can survive a couple of Low Kicks), and at least revenge kill Houndoom, while still having a SR user. on the Rhyperior issue, well, it's probably impossible to reliably counter the rock rhino without prediction, and you can revenge it with Kingdra, so i don't really think it's that much of a threat...