Metagross - Why the heck did you give it Flash? Get rid of that and Hyper Beam for Hammer Arm and HP Fire to get rid of steel types. You can change Meteor Mash for Bullet Punch, for Priority.
Milotic - Get rid of Hydro Pump, Blizzard and Water Pulse for Ice Beam, Surf and Toxic for attacking and stalling.
Rapidash - You should give it Megahorn and Wild Charge instead of Overheat and Fire Blast after that you can add either Morning Sun or Hypnosis for either Healing back or to stop the foe.
Kyurem - You rather change the whole moveset to
Ice Beam, Dragon Pulse, Focus Blast and Psychic.
Arcanine - Change Heat Wave to Wild Charge and you're good.
Porygon-Z - Change Thunder Wave to Psychic. That's it.
All-in-all, your team is good, only a few changes will make your team kick ass!