Hello apologies! Cool team you have here :)
I have a couple of recommendations to make. Right now, your team has problems with certain set up sweepers, particularly dragons, and like you said Volcarona. (Urugamosu). Unfortunately for dragons your best bet is to Bullet Punch with Scizor, which is quite dangerous as unless it's endgame you can become set-up fodder quite easily locked into a steel type move, (or flat out killed by Trapping Magnezone, a common partner to dragons).
Any Dragon type with a Lum berry can easily set up on Breloom, Rotom, or Jirachi and set up a Dragon Dance, allowing them to wreck havoc on the rest of your team (Haxorus and Dragonite especially, Salamence can be quite dangerous as well). Volcarona, of course, can set up on Scizor, Latias, and Breloom with Spore already used.
I 100% agree with Jirachi and recommend you switch to a scarfed Landorus. His perfect base speed, allowing him to barley outspeed all Dragon Dancing Dragons is awesome, allowing you to take them out with ease. Volcarona will no longer be an issue, as you can switch in on a Bug Buzz or Quiver Dance and threaten it. As you already have a good bulky water type (Rotom), Keldeo can be replaced easily. Landorus helps not only with your threats but can provide you with another momentum setter with his ability to U-Turn.
Landorus @ Choice Scarf
Sand Force
Naive/Hasty
252 Atk / 4 SpA / 252 Spe
-Earthquake
-Stone Edge
-U-turn
-HP Ice
EDIT:
Heh, I basically gave the exact same rate as Jirachi. Well, I hope you listen to our suggestions ^_^ Landorus would make a great addition to your team!