Hey kingken77,
Cool team! I see you're interested into shinies xD. I have to admit kd pretty much said everything, but nonetheless missed a couple of nitpicks.
The first nitpick relates to Heatran; I want to suggest giving him a Shuca Berry, using Explosion over Hidden Power Grass, and using a Timid Nature. This will give you an easier time against stall b/c you will have the freedom to switch moves. For Magnezone, use Hidden Power Ice over Fire and a Timid Nature. Hidden Power Ice with Thunder Wave will help you cripple and get rid of Scizor's and Tyranitar's checks. The grounds that come in on Magnezone will be taken care of for Tyranitar like Flygon and Gliscor. The power loss isn't huge and you need the speed to take care of all the pokemon in the 231 Spe range. Next, I want to suggest a better EV spread for Scizor, since your spread is inefficent atm only outspeeding Resttalk Gyarados, Agility Empoleon, and other SD Scizor. The spread you should use is 168 HP / 252 Atk / 88 Spe; it will outspeed certain pokemon I know around the 187 Spe range and most Scizor. I can't believe I'm saying this, but unless you know how to play around Machamp well I need to second keeping Psychic on Starmie. To end, I want to suggest using a Lum Berry on Tyranitar to get rid of crippling status from the likes of Toxic Spikes, which you don't stop atm, and such. You might even want to try Fire Punch on Tyranitar to get rid of Breloom on the switch if you have lum, but this isn't necessary.
Think that's it for now; hope it helps and good luck!
EDIT: Can't believe I didn't notice, you check all threats well except for Lucario! It can't really setup a Swords Dance, but can sweep most of your team without it. I hate scarfing two pokemon, but keeping one of Heatran, Magnezone, Tyranitar, or Scizor is probably the safe choice. Its your choice to which you scarf, but keep in mind that it will make your life a little difficult against stall. I would use Scarfzor just b/c it has U-turn to keep the momentum, but ultimately it might not be the greatest choice. All in all, testing is your best bet.