First, nice team! :) ooh! also, everything else in hide tags is ok, but take your team out of hide tags.
OK real stuff now: Replace Earthquake on Terrakion with Sacred Sword as an unSTABbed locked on Earthquake is just asking to be set up on. Most of the time, you'll just be using Close Combat though so not that important.
Giratina-O with Earthquake might be a problem, as its STABs hurt your team for heavy damage, and EQ gives it a lot of coverage on your team. (I'll think of something for this when i have time)
You have 3 Toxic users consider using other moves (eg U-Turn on Lando-T)
And 2 Thunder Wave users: Consider Roar>Thunder Wave on Dialga and Fire Blast>Flamethrower for the 2HKO on Ferrothorn in Rain