Physical Mewtwo can work wonders if you play it right, it's slightly unexpected, after all...
Mewtwo@Liechi/Salac/Lum Berry
EV: 252 Att, 252 Speed, 6 Sp Def
Nature: + Att, - Def
Brick Break
Shadow Ball
Earthquake/Rock Slide/Psychic
Ice Beam/Thunderbolt/Calm Mind/Earthquake
Brick Break deals with Dark types, Shadow Ball for other Psychics and Ghosts, and then insert your choice of physical or special move - it's not like Mewtwo needs any EV or nature bonus to it's Special Attack, after all.
Snorlax: Put some EV in Special Defence rather than Defence, and you may want to slip in some for Attack as well.
Snorlax@Leftovers
EV: 252 HP, 129 Att, 129 Sp Def
Nature: + Att, - Speed
Substitute
Focus Punch
Shadow Ball
Rest
Salamence: Drop Dragon Claw for Flamethrower, and Earthquake for Brick Break, otherwise fine. Adds a bit of Skarmbliss protection to your team
Blaziken - Blaziken's type combination is actually pretty detrimental to itself, adding more weaknesses than strengths.
Blaziken@Salac Berry
EV: 252 Att, 252 Speed, 6 Sp Def
Nature: + Speed, - Sp Att
Endure
Reversal
Shadow Ball/HP Ghost/Rock Slide
Overheat
Can't remember if Blaziken can learn Shadow Ball, if not use HP Ghost or Rock Slide instead
Tyranitar - you can do without Crunch, so leave it. Mixed sweeping with T-tar isn't so great.
Tyranitar@Lum/Salac/Liechi Berry
EV: 252 Att, 252 Speed, 6 Sp Def
Nature: + Att/Speed, - Sp Att
Dragon Dance
Earthquake
Rock Slide
Brick Break/HP Physical
Metagross: Really need to redistribute those EVs...
Metagross@Leftovers
EV: 129 HP, 129 Def, 252 Att
Nature: + Def/Att, - Sp Def
HP Steel
Earthquake
Shadow Ball
Agility/Psychic
Consider Psychic for anti-Weezing purposes.