First of all I would put farium z on magearna and leftovers on heatrans.
I would change the Zard Y set to this:
Charizard @ Charizardite Y
Ability: Blaze
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
- Flamethrower
- Solar Beam
- Focus Blast
- Roost
Kyurem is not really a bulky pokemon so i would...