Well small rate is all i can give your really Buddy but i would suggest this
Rotom-A give him Substitute over reflect gives him more longevity and allows him to survive super effective moves on switch ins.
Gyarados - I disagree with return i would run Eq or Bounce simply because your have rotom-A to deal with bulky waters
I see too things that would really hurt your team. Scizor can Ko TTar rotom and heatran and gallade to an extent with superpower bullet punch and pursuit though its unlikely they run all 3 on one set, they your Gyarados and gliscor can wall him to can extent bar that you have a slight suicune problem once rotom and and gallade die.
Because of this running Infernape over heatran and Rotom C over rotom A might help because gliscor already deals with Fire moves. and rotom C can have all the same moves just leaf storm over reflect if needed and couple that with your gyarados your have a fair few suicune counters.