This is a lot to pick at, so I'll only point out a few things.
Gliscor - Poison Heal is the superior Ability if you can obtain it, as most people don't use Charm-esque Moves. With that in mind, you may want to use a Stall set to take advantage of it's Bulk. Run Impish > Jolly if you Stall. EV's should be 252 Hp / 180 Def / 72 Spe. For the Moves, Toxic / Substitute / Protect / Earthquake works wonders.
Metagross - You'll probably want Stealth Rock > Zen Headbutt to help make Sweeps easier to come by. Spread should be 248 Hp / 252 Atk / 8 Spe to outspeed other Pokemon with the same Base Speed.
Skarmory - Whirlwind > Roar and Brave Bird > Fly. Use Impish aswell.
Turn the radio up, and we can have a good time