Maybe it's just me, but your team seems weak to fast Fighting attacks. Pokes like Specs Keldeo and Band Terrakion can dent every single poke of your team, and since your two resistances have no means of reliable recovery, they will be worn down quite fast even with resisted attacks. Skarmory can't take powerful Close Combats either, since it's 2HKO'd by many of them - Band Terrakion and to a lesser extent LO Lucario can do that. Of course, your Terrakion can revenge all of those, but they will hit once and switch out, quickly wearing down your resistances and absorbing your attacks with something else (Scarf Terrakion is not that hard to wall).
Also, Timid Venusaur in the sun completely dismantles your team after a bit of residual damage on Reuniclus is achieved. It can just switch into your Tentacruel, since Ice Beam needs Rocks to even have a chance to 2HKO, and Venusaur is likely to find a way to switch into Scald anyway. Or it could just switch into a resisted CC from your Terrakion. Then it gets a free Growth and proceed to destroy your team (Tentacruel can't stop it bar freeze hax since Giga Drain will heal Venusaur by roghly the same amount of damage Ice Beam deals).
Tornadus-T can be quite a pain too, since it's, again, handled only by Terrakion. It will ignore all of your hazards since you don't carry Stealth Rock (another big problem) and will regenerate any residual damage you can deal to it. Taunt can shut down Skarmory, while its Fighting coverage move of choice will hurt Zone (Hurricane + Superpower 2HKOs after SR).
At the moment I can't think of something that would fix all your problems, so I'll just let some ideas. First, Mamoswine can set up SR while being an annoyance for both Venusaur and Tornadus. However it compounds your weakness to Bullet Punch and Terrakion (unless it's caught in an EQ on the switch). Latias could also be a good idea, since it somewhat checks Terrakion if it chooses to Close Combat, is not OHKO'd by +2 Venusaur and can retaliate with HP Fire or Psyshock, although it won't OHKO (you need SR and 1 layer of Spikes to have a good chance to take down Venusaur). Finally, Liquid Ooze on Tentacruel can be a good idea, since Venusaur wouldn't be able to set up on it so easily while Giga Draining back lost HP, and also is quite annoying for those Ferrothorns that want to Leech Seed you. I'll reply again if I can find out some better ideas.
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