First OU Team: Lunch Box

Hey guys. I just made my first OU team but unfortunately it needs work.
I need help, improvements and tips. For now, this is my team: Lunch Box

Our special today is:



Now let's see each these pokemon's roles.

Skarmory
Nature: Impish
Ability: Sturdy
Item: Leftovers
EVs: 252 HP / 240 Def / 16 Spe
Moveset: Stealth Rock, Brave Bird, Roost, Whirlwind

Description:
Skarmory's job is to set up stealth rock and act as a physical wall. First, she will set up stealth rock then act according to the situation. Brave Bird is there to deal STAB damage and will recover from the recoil damage with leftovers. Roost is there to keep her healthy and continue her job. Whirlwind is there to blow away any counters or stat boosters.


Ninjask
Nature: Jolly
Ability: Speed Boost
Item: Leftovers
EVs: 176 HP / 252 Atk / 80 Spe
Moveset: X-Scissor, Substitute, Swords Dance, Baton Pass

Description:
Ninjask's job is to go for a substitute, swords dance, and baton pass over to my physical sweeper: Metagross. Ninjask will substitute, swords dance a couple of times (And with added Speed Boost) and either attempt to sweep using STAB X-Scissor against psychic types or neutrals or baton pass to Metagross. Ninjask has some mind-blowing speed and is sure to have the first move. Leftovers is there to heal some of his health after using substitute.


Gengar
Nature: Timid
Ability: Levitate
Item: Life Orb
EVs: 252 Sp.Atk/ 4 HP/ 252 Spe
Moveset: Focus Blast, Thunderbolt, Shadow Ball, Psychic(?)

Description:
Gengar is my special sweeper. Utilizing Life Orb and his 252 Sp. Atk EVs, this guy deserves a spot on my team as special sweeper. He has a variety of move types. Focus Blast is there for hitting Rock Types and Normal types that are physical walls. Thunderbolt takes care of water types such as Starmie and Garyados. Shadow Ball is there for STAB damage and super effectiveness against Ghost- and Psychic-types. Psychic is there because I couldn't find a suitable 4th move. I guess its there for fighting types like Machamp.


Togekiss
Nature: Bold
Ability: Serene Grace
Item: Leftovers
EVs: 252 HP / 188 Def / 68 SpD
Moveset: Aura Sphere, Air Slash, Thunder Wave, Roost

Description:
The awesome Togekiss. His role is to give the opponent some annoyance to deal with. Sending off a thunder wave to those who aren't immune to it and using Air Slash for STAB and flinching (W/ Serene Grace) my opponent won't have much of a chance to act against me. They will find little chance on attacking or reacting and hoping that they will switch out. Aura Sphere is there as a move for damage. Air Slash is for flinching and STAB. Thunder Wave will be used before executing Air Slash. Roost is there for reliable healing. Leftovers is for minor healing. Togekiss is also my bulk so yeah.


Metagross
Nature: Adamant
Ability: Clear Body
Item: ?
EVs: I don't know. I got it in a tade and they didn't know the EVs.
Moveset: Meteor Mash, Psychic, Earthquake, Bullet Punch

Description:
This guy is unknown. I have know idea what the EVs are but I'll just wing it. My item would be a choice item. Band for damage or Scarf for speed. I don't think scarf would do much because Metagross has pitiful speed so I don't think it has Speed EVs. Either one is fine. He will be my temporary physical sweeper. With Ninjask at his side to pass speed and attack boosts to, Metagross will be a fast moving sweeper. Oh my, I guess I'll be going with choice band for maximum damage then. Meteor Mash is for STAB, Psychic is for.. I don't know. It was there. Earthquake for STAB and a reliable strong move but I am in trouble if my opponent throws out a flying type or a Levitater. Bullet Punch for first strike move and STAB.


Blissey
Nature: Bold
Ability: Natural Cure
Item: Leftovers
Evs: 252 HP / 252 Def / 4 Spe
Moveset: Aromatherapy, Softboiled, Flamethrower, Toxic

Description:
Due to the lack of Seismic Toss, Blissey won't be attack much. Blissey cts as a cleric, healing my team of any status problems. using Aromatherapy. Softboiled for reliable healing and Flamethrower for miserable damage (Due to lack of Seismic Toss) Toxic is there to well, wear down some damage. With Skarmory as a partner, we have the SkarmBliss duo. Skarmory will absorb physical attacks while Blissey absorbs special attacks. One reason why I got Blissey: Skarmory + Special Sweeper = Dead. The defense EVs are there to make up for its terrible defense.


So yeah thats it. I will take any substitutes and such. Strategy, Tips, etc is wanted. I will keep Skarmory and Blissey on there simply because of SkarmBliss.

I think that Ninjask and Skarmory should switch spots because of the former's 4x Stealth Rock weakness. Jolly is overkill on Ninjask, so switching its nature to Adamant might be worth considering.

Gengar: Hidden Power (Fire) can go over Psychic to let it deal with Scizor and Forretress more easily. Explosion can also be used if you see an opposing Blissey, if Gengar's Hidden Power type is something else.

Metagross: Why are you using Psychic on an Adamant Pokemon? Zen Headbutt can go in its place. If you don't know Metagross' EVs, use EV-reducing berries and re-EV train it.

When I traded for Metagross it had Psychic. I will definitely get Zen Headbutt.

Ninjask wouldn't be sweeping but I'll consider Adamant nature.

For Gengar, I might try to get Explosion.

Thanks for the critique.

Metagross @ Leftovers / Life Orb (Since he's gonna surely benefit from Ninjask's Speed Boost [SB] and Swords Dance [SD])
252 Attack 252 Speed 4 HP/Def/SDef
~Zen Headbutt
~Meteor Mash
~Thunderpunch
~Earthquake
*Life Orb for more power or Leftovers for survival.

Zen Headbutt and Meteor Mash are you main STAB moves. With two SB's coming from Ninask and one SD, it can outspeed and OHKO Flygon with MM which is sometimes used to counter it. It can also outspeed other Infernapes and Heatrans with minimum speed or non-scarfed.

Your team lacks a revenge killer and it may have troubles maintaining Ninjask. IF in not-so-good circumstances that Ninjask would faint, you might get something that revenge kills like Heatran or Flygon. Flygon has its advantages due to the access to U-Turn which can dispose of Psychic types or just scout around. Both are also good switches to incoming fire attacks aimed at Skarmory, Metagross and Ninjask. Flygon would just laugh it off while Heatran absorbs it.

You really won't need another defensive wall since you already have Blissey. What you need is to maintain the survivability of your 'mons, like having Wish Support. Heal Bell on Blissey isn't bad either as switching it out to get stall and Heal Bell to remove statuses inflicted. Gengar isn't bad, but it's lack of bulk make your team more fragile. A ScarfTran could get 3 out of 6 of your 'mons (Metagross, Ninjask, Skarmory). Machamp can be easily dealt with a single Zen Headbutt coming from a boosted Metagross, so you really don't need Psychic on Gengar. Get HP Fire or Explosion like what Platinum Dude has suggested. Not to mention that Spiritomb can stall your whole team with Rest and Sleep Talk, except when your Metagross gets a boost.

Ok then.
So do you suggest who I should switch for Flygon?

From the looks of it, I will have to retrain Metagross myself.

Thanks Musica.