Hmm, UU teams just seem to get no love in being rated these days.
A few things stand out immediately to me about your team, so I'd like to offer a few simple changes first.
-With prior damage to some of your team members, I would not put it past heracross to complete a scarf moxie sweep of your team with megahorn. SD hera could potentially do the same if Tornadus-I goes down. For this reason, I hate to ask, but please swap fire punch for aerial ace on flygon. It's just not worth hitting bronzong for SE damage when you're still doing stuff all to the bell, and firepunch from scarfgon doesn't come nearly close enough to kill heracross (a 2HKO even with full hazards up).
-As for frosslass, I'd rather that were not used as a sashlead unless you intend to place another ghost pokemon in your team. Your not hyperoffensive here, so it's far too easy for any of UU's spinners to come in and undo your hard work. Worse yet, you have no destiny bond so you shouldn't even be entertaining the idea of focus sash. You are probably better off going with the utility moveset and EV spread from the site http://www.smogon.com/bw/pokemon/froslass
Cresselia is bulky enough to paralyse anything you need to be paralysed, while also getting rid of scarfgon if you can lock them into outrage. Frosslass can use pain split to further wear down foes and heal itself.
Finally, I would be very interested to know how this team deals with SubCM Raikou? Your only phazer in empoleon cannot keep taking thunderbolts, if it can even take a +1 thunderbolt to begin with, cresselia cannot keep breaking the sub after several CM, and I see nothing else that can reliably take hits from either thunderbolt, or hidden power ice in flygon's case. I hate to get rid of prankster taunt, but I wonder, since you seem keen on using life orb, if Rotom-H would help here. Maybe a set with...
Rotom-H @ Life Orb
252 SpAtk, 252 HP/Spe, 4 SpD
EV's depend on whether you wish for it to hit hard and fast or if you want some bulk. Pain Split would let you recover off hazard damage from SR while also adding passive damage. This would help with your threat list quite a bit as Sableye can't burn it while risking Parahax from discharge, Zapdos will hate having all of its attacks resisted and its subs broken (watch out for the odd set carrying toxic though). Honchkrow is still difficult to deal with after boosting but you can attempt to diminish the low PP of suckerpunch with pain split, while resisting brave bird. HP ground with life orb will continually break raikou's subs at +1 while it cannot do much to you in return. If you want, you can use leftovers, but just be sure to have special attack maxed out to ensure the breaking of those substitutes.
Downside to that is that you are going to be stuck playing guessing games against heracross, but generally people are silly and leave heracross in against flygon, who with aerial ace will revenge them if it does kill something. Similar to chandelure, particularly the SubCM set, but you may just have to live with that...
Hope my changes help. Also one last thing; Honchkrow normally rely on suckerpunch as the sole dark attack, so cresselia should be able to cripple it with paralysis, so you can switch to something who can deal with it. I suppose if it's last move is substitute though...
Additional note: I think cresselia gets psycho shift in its movepool if you find toxic to be a hassle. Wouldn't know what move to drop for it however.