The list looks pretty solid, but I have a few suggestions. I think you can do with 1 less of each Mewtwo and Smeargle. Playing more than 1 Mewtwo significantly increases the risk of a Mewtwo start, which you don't want. Mewtwo is too easily KOed by another Mewtwo, and you don't want to give up 2 prizes that easily. Darkrai and Tornadus are pretty effective in dealing with opposing Mewtwos, so you really only need a Mewtwo of your own to prevent your opponent from loading a Mewtwo up with energy and steamrolling you.
The Smeargles are great, but less important in a Tornadus build. Because you can attack T1 pretty easily with Tornadus/DCE, it's less important to get a T1 Dark Spear, which is the principal reason for running a high Smeargle count. I've been using 2 Smeargles in my Darkrai/Tornadus list, and I can't think of a time when I wished I had another Smeargle. If you do decide to run a 3rd Smeargle, however, you definitely should add a switch to take advantage of the Smeargles.
As for the Tornadus count, I think that really is a metagame call. If Eel decks are still prominent in your metagame, I think 3 Tornadus is risky because they are too easily KOed by Thudurus/Zekrom/Raichou. On the other hand, if Eel play declines, which it may, 3 Tornadus is great because it gives you the flexibility to shift completely to Tornadus when facing fighting decks. I personally play with 2 Tornadus and it's worked fine.
On the T/S/S lines, I think you need to beef up your draw engine, either by adding a couple more draw supporters or a couple more Random Receivers. Even with the Smeargle, I think 12 draw supporters/Random Receivers is a minimum for consistency. How you whack it up is a matter of preference, but I would include a couple of N. The card is just too good. I've personally tried to reduce my Juniper line because my list has a number of 2-of trainers that I don't want to discard. I've compensated by using 3 Engineer's Adjustments (I reduced my PONT count to 3 also), which gives me another way to discard an energy, and nets me 4 cards on the draw. I'm not completely sold on that approach yet, but it's worked pretty well in testing so far.
I don't think you need the Dark Claw in the deck. The extra 20 damage is great (especially on an Eviolited Pokemon), but I think it's more important to keep your Darkari/Tornadi alive. You could use those 2 spaces to increase your Eviolite count and/or to add 1 or 2 SSU/Potions. You also could consider adding PlusPowers, which can be used with Tornadus as well as Darkrai, while still getting the benefit of Eviolite.
Finally, 4 Skyarrow is overkill. A lot of decks are running Skyarrow now, so there's a good chance your opponent will play it for you. I'm currently running 2 (with 2 Switches), and it's been fine. If more fighting decks pop up using Ruins of Alph, or there end up being more decks not playing Skyarrow, I think a 3rd Skyarrow probably would be necessary. Until then, however, I'm more likely to increase my Switch count than my Skyarrow count.
I hope this is helpful. There are a lot of ways to skin this cat, so much of it comes down to play style and preference. I play my deck with a healing focus (SSU/Max Potion), but you should look at the winning decklist from the Finnish Nationals, which was designed for energy denial. Whichever way you go, however, consistency is king and, if nothing else, you should up your draw supporter/Random Receiver count. Good luck.
