Wow, this team is almost flawless.
I suggest flipping the HP and SpD for Azu around. You'll be able to at least tank 1 Garchomp EQ easier.
I'd also run Taunt or Roar over Flash Cannon on Heatran. While it is STAB, Azumarill hurts rock types enough and most fairies (Sylveon, Florges) don't...