On the surface you have good matchups here. Dragonite vs. Gyarados is a win for you, and if he switches to Latias, you're still ahead because you have the faster DB/DC moveset. Mewtwo would also be very effective against Latias, as would your Ttar. The only matchup that really worries me is Ttar against Scizor, but you should even win that because of the huge CP discrepancy.
So how did the battle go? Where do you think you weren't optimal?